overload.t revision 1.4 
1#!./perl -T
2
3BEGIN {
4    chdir 't' if -d 't';
5    @INC = '../lib';
6    require Config;
7    if (($Config::Config{'extensions'} !~ m!\bList/Util\b!) ){
8	print "1..0 # Skip -- Perl configured without List::Util module\n";
9	exit 0;
10    }
11}
12
13package Oscalar;
14use overload ( 
15				# Anonymous subroutines:
16'+'	=>	sub {new Oscalar $ {$_[0]}+$_[1]},
17'-'	=>	sub {new Oscalar
18		       $_[2]? $_[1]-${$_[0]} : ${$_[0]}-$_[1]},
19'<=>'	=>	sub {new Oscalar
20		       $_[2]? $_[1]-${$_[0]} : ${$_[0]}-$_[1]},
21'cmp'	=>	sub {new Oscalar
22		       $_[2]? ($_[1] cmp ${$_[0]}) : (${$_[0]} cmp $_[1])},
23'*'	=>	sub {new Oscalar ${$_[0]}*$_[1]},
24'/'	=>	sub {new Oscalar 
25		       $_[2]? $_[1]/${$_[0]} :
26			 ${$_[0]}/$_[1]},
27'%'	=>	sub {new Oscalar
28		       $_[2]? $_[1]%${$_[0]} : ${$_[0]}%$_[1]},
29'**'	=>	sub {new Oscalar
30		       $_[2]? $_[1]**${$_[0]} : ${$_[0]}-$_[1]},
31
32qw(
33""	stringify
340+	numify)			# Order of arguments insignificant
35);
36
37sub new {
38  my $foo = $_[1];
39  bless \$foo, $_[0];
40}
41
42sub stringify { "${$_[0]}" }
43sub numify { 0 + "${$_[0]}" }	# Not needed, additional overhead
44				# comparing to direct compilation based on
45				# stringify
46
47package main;
48
49$| = 1;
50BEGIN { require './test.pl'; require './charset_tools.pl' }
51plan tests => 5363;
52
53use Scalar::Util qw(tainted);
54
55$a = new Oscalar "087";
56$b= "$a";
57
58is($b, $a);
59is($b, "087");
60is(ref $a, "Oscalar");
61is($a, $a);
62is($a, "087");
63
64$c = $a + 7;
65
66is(ref $c, "Oscalar");
67isnt($c, $a);
68is($c, "94");
69
70$b=$a;
71
72is(ref $a, "Oscalar");
73
74$b++;
75
76is(ref $b, "Oscalar");
77is($a, "087");
78is($b, "88");
79is(ref $a, "Oscalar");
80
81$c=$b;
82$c-=$a;
83
84is(ref $c, "Oscalar");
85is($a, "087");
86is($c, "1");
87is(ref $a, "Oscalar");
88
89$b=1;
90$b+=$a;
91
92is(ref $b, "Oscalar");
93is($a, "087");
94is($b, "88");
95is(ref $a, "Oscalar");
96
97eval q[ package Oscalar; use overload ('++' => sub { $ {$_[0]}++;$_[0] } ) ];
98
99$b=$a;
100
101is(ref $a, "Oscalar");
102
103$b++;
104
105is(ref $b, "Oscalar");
106is($a, "087");
107is($b, "88");
108is(ref $a, "Oscalar");
109
110package Oscalar;
111$dummy=bless \$dummy;		# Now cache of method should be reloaded
112package main;
113
114$b=$a;
115$b++;				
116
117is(ref $b, "Oscalar");
118is($a, "087");
119is($b, "88");
120is(ref $a, "Oscalar");
121
122undef $b;			# Destroying updates tables too...
123
124eval q[package Oscalar; use overload ('++' => sub { $ {$_[0]} += 2; $_[0] } ) ];
125
126$b=$a;
127
128is(ref $a, "Oscalar");
129
130$b++;
131
132is(ref $b, "Oscalar");
133is($a, "087");
134is($b, "89");
135is(ref $a, "Oscalar");
136
137package Oscalar;
138$dummy=bless \$dummy;		# Now cache of method should be reloaded
139package main;
140
141$b++;				
142
143is(ref $b, "Oscalar");
144is($a, "087");
145is($b, "91");
146is(ref $a, "Oscalar");
147
148$b=$a;
149$b++;
150
151is(ref $b, "Oscalar");
152is($a, "087");
153is($b, "89");
154is(ref $a, "Oscalar");
155
156
157ok($b? 1:0);
158
159eval q[ package Oscalar; use overload ('=' => sub {$main::copies++; 
160						   package Oscalar;
161						   local $new=$ {$_[0]};
162						   bless \$new } ) ];
163
164$b=new Oscalar "$a";
165
166is(ref $b, "Oscalar");
167is($a, "087");
168is($b, "087");
169is(ref $a, "Oscalar");
170
171$b++;
172
173is(ref $b, "Oscalar");
174is($a, "087");
175is($b, "89");
176is(ref $a, "Oscalar");
177is($copies, undef);
178
179$b+=1;
180
181is(ref $b, "Oscalar");
182is($a, "087");
183is($b, "90");
184is(ref $a, "Oscalar");
185is($copies, undef);
186
187$b=$a;
188$b+=1;
189
190is(ref $b, "Oscalar");
191is($a, "087");
192is($b, "88");
193is(ref $a, "Oscalar");
194is($copies, undef);
195
196$b=$a;
197$b++;
198
199is(ref $b, "Oscalar");
200is($a, "087");
201is($b, "89");
202is(ref $a, "Oscalar");
203is($copies, 1);
204
205eval q[package Oscalar; use overload ('+=' => sub {$ {$_[0]} += 3*$_[1];
206						   $_[0] } ) ];
207$c=new Oscalar;			# Cause rehash
208
209$b=$a;
210$b+=1;
211
212is(ref $b, "Oscalar");
213is($a, "087");
214is($b, "90");
215is(ref $a, "Oscalar");
216is($copies, 2);
217
218$b+=$b;
219
220is(ref $b, "Oscalar");
221is($b, "360");
222is($copies, 2);
223$b=-$b;
224
225is(ref $b, "Oscalar");
226is($b, "-360");
227is($copies, 2);
228
229$b=abs($b);
230
231is(ref $b, "Oscalar");
232is($b, "360");
233is($copies, 2);
234
235$b=abs($b);
236
237is(ref $b, "Oscalar");
238is($b, "360");
239is($copies, 2);
240
241eval q[package Oscalar; 
242       use overload ('x' => sub {new Oscalar ( $_[2] ? "_.$_[1]._" x $ {$_[0]}
243					      : "_.${$_[0]}._" x $_[1])}) ];
244
245$a=new Oscalar "yy";
246$a x= 3;
247is($a, "_.yy.__.yy.__.yy._");
248
249eval q[package Oscalar; 
250       use overload ('.' => sub {new Oscalar ( $_[2] ? 
251					      "_.$_[1].__.$ {$_[0]}._"
252					      : "_.$ {$_[0]}.__.$_[1]._")}) ];
253
254$a=new Oscalar "xx";
255
256is("b${a}c", "_._.b.__.xx._.__.c._");
257
258# Check inheritance of overloading;
259{
260  package OscalarI;
261  @ISA = 'Oscalar';
262}
263
264$aI = new OscalarI "$a";
265is(ref $aI, "OscalarI");
266is("$aI", "xx");
267is($aI, "xx");
268is("b${aI}c", "_._.b.__.xx._.__.c._");
269
270# Here we test that both "no overload" and
271# blessing to a package update hash
272
273eval "package Oscalar; no overload '.'";
274
275is("b${a}", "bxx");
276$x="1";
277bless \$x, Oscalar;
278is("b${a}c", "bxxc");
279new Oscalar 1;
280is("b${a}c", "bxxc");
281
282# Negative overloading:
283
284$na = eval { ~$a };
285like($@, qr/no method found/);
286
287# Check AUTOLOADING:
288
289*Oscalar::AUTOLOAD = 
290  sub { *{"Oscalar::$AUTOLOAD"} = sub {"_!_" . shift() . "_!_"} ;
291	goto &{"Oscalar::$AUTOLOAD"}};
292
293eval "package Oscalar; sub comple; use overload '~' => 'comple'";
294
295$na = eval { ~$a };
296is($@, '');
297
298bless \$x, Oscalar;
299
300$na = eval { ~$a };		# Hash updated
301warn "'$na', $@" if $@;
302ok !$@;
303is($na, '_!_xx_!_');
304
305$na = 0;
306
307$na = eval { ~$aI };
308is($@, '');
309
310bless \$x, OscalarI;
311
312$na = eval { ~$aI };
313print $@;
314
315ok(!$@);
316is($na, '_!_xx_!_');
317
318eval "package Oscalar; sub rshft; use overload '>>' => 'rshft'";
319
320$na = eval { $aI >> 1 };
321is($@, '');
322
323bless \$x, OscalarI;
324
325$na = 0;
326
327$na = eval { $aI >> 1 };
328print $@;
329
330ok(!$@);
331is($na, '_!_xx_!_');
332
333# warn overload::Method($a, '0+'), "\n";
334is(overload::Method($a, '0+'), \&Oscalar::numify);
335is(overload::Method($aI,'0+'), \&Oscalar::numify);
336ok(overload::Overloaded($aI));
337ok(!overload::Overloaded('overload'));
338
339ok(! defined overload::Method($aI, '<<'));
340ok(! defined overload::Method($a, '<'));
341
342like (overload::StrVal($aI), qr/^OscalarI=SCALAR\(0x[\da-fA-F]+\)$/);
343is(overload::StrVal(\$aI), "@{[\$aI]}");
344
345# Check overloading by methods (specified deep in the ISA tree).
346{
347  package OscalarII;
348  @ISA = 'OscalarI';
349  sub Oscalar::lshft {"_<<_" . shift() . "_<<_"}
350  eval "package OscalarI; use overload '<<' => 'lshft', '|' => 'lshft'";
351}
352
353$aaII = "087";
354$aII = \$aaII;
355bless $aII, 'OscalarII';
356bless \$fake, 'OscalarI';		# update the hash
357is(($aI | 3), '_<<_xx_<<_');
358# warn $aII << 3;
359is(($aII << 3), '_<<_087_<<_');
360
361{
362  BEGIN { $int = 7; overload::constant 'integer' => sub {$int++; shift}; }
363  $out = 2**10;
364}
365is($int, 9);
366is($out, 1024);
367is($int, 9);
368{
369  BEGIN { overload::constant 'integer' => sub {$int++; shift()+1}; }
370  eval q{$out = 42};
371}
372is($int, 10);
373is($out, 43);
374
375$foo = 'foo';
376$foo1 = 'f\'o\\o';
377{
378  BEGIN { $q = $qr = 7; 
379	  overload::constant 'q' => sub {$q++; push @q, shift, ($_[1] || 'none'); shift},
380			     'qr' => sub {$qr++; push @qr, shift, ($_[1] || 'none'); shift}; }
381  $out = 'foo';
382  $out1 = 'f\'o\\o';
383  $out2 = "a\a$foo,\,";
384  /b\b$foo.\./;
385}
386
387is($out, 'foo');
388is($out, $foo);
389is($out1, 'f\'o\\o');
390is($out1, $foo1);
391is($out2, "a\afoo,\,");
392is("@q", "foo q f'o\\\\o q a\\a qq ,\\, qq");
393is($q, 11);
394is("@qr", "b\\b qq .\\. qq");
395is($qr, 9);
396
397{
398  $_ = '!<b>!foo!<-.>!';
399  BEGIN { overload::constant 'q' => sub {push @q1, shift, ($_[1] || 'none'); "_<" . (shift) . ">_"},
400			     'qr' => sub {push @qr1, shift, ($_[1] || 'none'); "!<" . (shift) . ">!"}; }
401  $out = 'foo';
402  $out1 = 'f\'o\\o';
403  $out2 = "a\a$foo,\,";
404  $res = /b\b$foo.\./;
405  $a = <<EOF;
406oups
407EOF
408  $b = <<'EOF';
409oups1
410EOF
411  $c = bareword;
412  m'try it';
413  s'first part'second part';
414  s/yet another/tail here/;
415  tr/A-Z/a-z/;
416}
417
418is($out, '_<foo>_');
419is($out1, '_<f\'o\\o>_');
420is($out2, "_<a\a>_foo_<,\,>_");
421is("@q1", "foo q f'o\\\\o q a\\a qq ,\\, qq oups
422 qq oups1
423 q second part q tail here s A-Z tr a-z tr");
424is("@qr1", "b\\b qq .\\. qq try it q first part q yet another qq");
425is($res, 1);
426is($a, "_<oups
427>_");
428is($b, "_<oups1
429>_");
430is($c, "bareword");
431
432{
433  package symbolic;		# Primitive symbolic calculator
434  use overload nomethod => \&wrap, '""' => \&str, '0+' => \&num,
435      '=' => \&cpy, '++' => \&inc, '--' => \&dec;
436
437  sub new { shift; bless ['n', @_] }
438  sub cpy {
439    my $self = shift;
440    bless [@$self], ref $self;
441  }
442  sub inc { $_[0] = bless ['++', $_[0], 1]; }
443  sub dec { $_[0] = bless ['--', $_[0], 1]; }
444  sub wrap {
445    my ($obj, $other, $inv, $meth) = @_;
446    if ($meth eq '++' or $meth eq '--') {
447      @$obj = ($meth, (bless [@$obj]), 1); # Avoid circular reference
448      return $obj;
449    }
450    ($obj, $other) = ($other, $obj) if $inv;
451    bless [$meth, $obj, $other];
452  }
453  sub str {
454    my ($meth, $a, $b) = @{+shift};
455    $a = 'u' unless defined $a;
456    if (defined $b) {
457      "[$meth $a $b]";
458    } else {
459      "[$meth $a]";
460    }
461  } 
462  my %subr = ( 'n' => sub {$_[0]} );
463  foreach my $op (split " ", $overload::ops{with_assign}) {
464    $subr{$op} = $subr{"$op="} = eval "sub {shift() $op shift()}";
465  }
466  my @bins = qw(binary 3way_comparison num_comparison str_comparison);
467  foreach my $op (split " ", "@overload::ops{ @bins }") {
468    $subr{$op} = eval "sub {shift() $op shift()}";
469  }
470  foreach my $op (split " ", "@overload::ops{qw(unary func)}") {
471    $subr{$op} = eval "sub {$op shift()}";
472  }
473  $subr{'++'} = $subr{'+'};
474  $subr{'--'} = $subr{'-'};
475  
476  sub num {
477    my ($meth, $a, $b) = @{+shift};
478    my $subr = $subr{$meth} 
479      or die "Do not know how to ($meth) in symbolic";
480    $a = $a->num if ref $a eq __PACKAGE__;
481    $b = $b->num if ref $b eq __PACKAGE__;
482    $subr->($a,$b);
483  }
484  sub TIESCALAR { my $pack = shift; $pack->new(@_) }
485  sub FETCH { shift }
486  sub nop {  }		# Around a bug
487  sub vars { my $p = shift; tie($_, $p), $_->nop foreach @_; }
488  sub STORE { 
489    my $obj = shift; 
490    $#$obj = 1; 
491    $obj->[1] = shift;
492  }
493}
494
495{
496  my $foo = new symbolic 11;
497  my $baz = $foo++;
498  is((sprintf "%d", $foo), '12');
499  is((sprintf "%d", $baz), '11');
500  my $bar = $foo;
501  $baz = ++$foo;
502  is((sprintf "%d", $foo), '13');
503  is((sprintf "%d", $bar), '12');
504  is((sprintf "%d", $baz), '13');
505  my $ban = $foo;
506  $baz = ($foo += 1);
507  is((sprintf "%d", $foo), '14');
508  is((sprintf "%d", $bar), '12');
509  is((sprintf "%d", $baz), '14');
510  is((sprintf "%d", $ban), '13');
511  $baz = 0;
512  $baz = $foo++;
513  is((sprintf "%d", $foo), '15');
514  is((sprintf "%d", $baz), '14');
515  is("$foo", '[++ [+= [++ [++ [n 11] 1] 1] 1] 1]');
516}
517
518{
519  my $iter = new symbolic 2;
520  my $side = new symbolic 1;
521  my $cnt = $iter;
522  
523  while ($cnt) {
524    $cnt = $cnt - 1;		# The "simple" way
525    $side = (sqrt(1 + $side**2) - 1)/$side;
526  }
527  my $pi = $side*(2**($iter+2));
528  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
529  is((sprintf "%f", $pi), '3.182598');
530}
531
532{
533  my $iter = new symbolic 2;
534  my $side = new symbolic 1;
535  my $cnt = $iter;
536  
537  while ($cnt--) {
538    $side = (sqrt(1 + $side**2) - 1)/$side;
539  }
540  my $pi = $side*(2**($iter+2));
541  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
542  is((sprintf "%f", $pi), '3.182598');
543}
544
545{
546  my ($a, $b);
547  symbolic->vars($a, $b);
548  my $c = sqrt($a**2 + $b**2);
549  $a = 3; $b = 4;
550  is((sprintf "%d", $c), '5');
551  $a = 12; $b = 5;
552  is((sprintf "%d", $c), '13');
553}
554
555{
556  package symbolic1;		# Primitive symbolic calculator
557  # Mutator inc/dec
558  use overload nomethod => \&wrap, '""' => \&str, '0+' => \&num, '=' => \&cpy;
559
560  sub new { shift; bless ['n', @_] }
561  sub cpy {
562    my $self = shift;
563    bless [@$self], ref $self;
564  }
565  sub wrap {
566    my ($obj, $other, $inv, $meth) = @_;
567    if ($meth eq '++' or $meth eq '--') {
568      @$obj = ($meth, (bless [@$obj]), 1); # Avoid circular reference
569      return $obj;
570    }
571    ($obj, $other) = ($other, $obj) if $inv;
572    bless [$meth, $obj, $other];
573  }
574  sub str {
575    my ($meth, $a, $b) = @{+shift};
576    $a = 'u' unless defined $a;
577    if (defined $b) {
578      "[$meth $a $b]";
579    } else {
580      "[$meth $a]";
581    }
582  } 
583  my %subr = ( 'n' => sub {$_[0]} );
584  foreach my $op (split " ", $overload::ops{with_assign}) {
585    $subr{$op} = $subr{"$op="} = eval "sub {shift() $op shift()}";
586  }
587  my @bins = qw(binary 3way_comparison num_comparison str_comparison);
588  foreach my $op (split " ", "@overload::ops{ @bins }") {
589    $subr{$op} = eval "sub {shift() $op shift()}";
590  }
591  foreach my $op (split " ", "@overload::ops{qw(unary func)}") {
592    $subr{$op} = eval "sub {$op shift()}";
593  }
594  $subr{'++'} = $subr{'+'};
595  $subr{'--'} = $subr{'-'};
596  
597  sub num {
598    my ($meth, $a, $b) = @{+shift};
599    my $subr = $subr{$meth} 
600      or die "Do not know how to ($meth) in symbolic";
601    $a = $a->num if ref $a eq __PACKAGE__;
602    $b = $b->num if ref $b eq __PACKAGE__;
603    $subr->($a,$b);
604  }
605  sub TIESCALAR { my $pack = shift; $pack->new(@_) }
606  sub FETCH { shift }
607  sub vars { my $p = shift; tie($_, $p) foreach @_; }
608  sub STORE { 
609    my $obj = shift; 
610    $#$obj = 1; 
611    $obj->[1] = shift;
612  }
613}
614
615{
616  my $foo = new symbolic1 11;
617  my $baz = $foo++;
618  is((sprintf "%d", $foo), '12');
619  is((sprintf "%d", $baz), '11');
620  my $bar = $foo;
621  $baz = ++$foo;
622  is((sprintf "%d", $foo), '13');
623  is((sprintf "%d", $bar), '12');
624  is((sprintf "%d", $baz), '13');
625  my $ban = $foo;
626  $baz = ($foo += 1);
627  is((sprintf "%d", $foo), '14');
628  is((sprintf "%d", $bar), '12');
629  is((sprintf "%d", $baz), '14');
630  is((sprintf "%d", $ban), '13');
631  $baz = 0;
632  $baz = $foo++;
633  is((sprintf "%d", $foo), '15');
634  is((sprintf "%d", $baz), '14');
635  is("$foo", '[++ [+= [++ [++ [n 11] 1] 1] 1] 1]');
636}
637
638{
639  my $iter = new symbolic1 2;
640  my $side = new symbolic1 1;
641  my $cnt = $iter;
642  
643  while ($cnt) {
644    $cnt = $cnt - 1;		# The "simple" way
645    $side = (sqrt(1 + $side**2) - 1)/$side;
646  }
647  my $pi = $side*(2**($iter+2));
648  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
649  is((sprintf "%f", $pi), '3.182598');
650}
651
652{
653  my $iter = new symbolic1 2;
654  my $side = new symbolic1 1;
655  my $cnt = $iter;
656  
657  while ($cnt--) {
658    $side = (sqrt(1 + $side**2) - 1)/$side;
659  }
660  my $pi = $side*(2**($iter+2));
661  is("$side", '[/ [- [sqrt [+ 1 [** [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]] 2]]] 1] [/ [- [sqrt [+ 1 [** [n 1] 2]]] 1] [n 1]]]');
662  is((sprintf "%f", $pi), '3.182598');
663}
664
665{
666  my ($a, $b);
667  symbolic1->vars($a, $b);
668  my $c = sqrt($a**2 + $b**2);
669  $a = 3; $b = 4;
670  is((sprintf "%d", $c), '5');
671  $a = 12; $b = 5;
672  is((sprintf "%d", $c), '13');
673}
674
675{
676  package two_face;		# Scalars with separate string and
677                                # numeric values.
678  sub new { my $p = shift; bless [@_], $p }
679  use overload '""' => \&str, '0+' => \&num, fallback => 1;
680  sub num {shift->[1]}
681  sub str {shift->[0]}
682}
683
684{
685  my $seven = new two_face ("vii", 7);
686  is((sprintf "seven=$seven, seven=%d, eight=%d", $seven, $seven+1),
687	'seven=vii, seven=7, eight=8');
688  is(scalar ($seven =~ /i/), '1');
689}
690
691{
692  package sorting;
693  use overload 'cmp' => \&comp;
694  sub new { my ($p, $v) = @_; bless \$v, $p }
695  sub comp { my ($x,$y) = @_; ($$x * 3 % 10) <=> ($$y * 3 % 10) or $$x cmp $$y }
696}
697{
698  my @arr = map sorting->new($_), 0..12;
699  my @sorted1 = sort @arr;
700  my @sorted2 = map $$_, @sorted1;
701  is("@sorted2", '0 10 7 4 1 11 8 5 12 2 9 6 3');
702}
703{
704  package iterator;
705  use overload '<>' => \&iter;
706  sub new { my ($p, $v) = @_; bless \$v, $p }
707  sub iter { my ($x) = @_; return undef if $$x < 0; return $$x--; }
708}
709
710{
711  my $iter = iterator->new(5);
712  my $acc = '';
713  my $out;
714  $acc .= " $out" while $out = <${iter}>;
715  is($acc, ' 5 4 3 2 1 0');
716  $iter = iterator->new(5);
717  is(scalar <${iter}>, '5');
718  $acc = '';
719  $acc .= " $out" while $out = <$iter>;
720  is($acc, ' 4 3 2 1 0');
721}
722{
723  package deref;
724  use overload '%{}' => \&hderef, '&{}' => \&cderef, 
725    '*{}' => \&gderef, '${}' => \&sderef, '@{}' => \&aderef;
726  sub new { my ($p, $v) = @_; bless \$v, $p }
727  sub deref {
728    my ($self, $key) = (shift, shift);
729    my $class = ref $self;
730    bless $self, 'deref::dummy'; # Disable overloading of %{} 
731    my $out = $self->{$key};
732    bless $self, $class;	# Restore overloading
733    $out;
734  }
735  sub hderef {shift->deref('h')}
736  sub aderef {shift->deref('a')}
737  sub cderef {shift->deref('c')}
738  sub gderef {shift->deref('g')}
739  sub sderef {shift->deref('s')}
740}
741{
742  my $deref = bless { h => { foo => 5 , fake => 23 },
743		      c => sub {return shift() + 34},
744		      's' => \123,
745		      a => [11..13],
746		      g => \*srt,
747		    }, 'deref';
748  # Hash:
749  my @cont = sort %$deref;
750  if ("\t" eq "\011") { # ASCII
751      is("@cont", '23 5 fake foo');
752  } 
753  else {                # EBCDIC alpha-numeric sort order
754      is("@cont", 'fake foo 23 5');
755  }
756  my @keys = sort keys %$deref;
757  is("@keys", 'fake foo');
758  my @val = sort values %$deref;
759  is("@val", '23 5');
760  is($deref->{foo}, 5);
761  is(defined $deref->{bar}, '');
762  my $key;
763  @keys = ();
764  push @keys, $key while $key = each %$deref;
765  @keys = sort @keys;
766  is("@keys", 'fake foo');
767  is(exists $deref->{bar}, '');
768  is(exists $deref->{foo}, 1);
769  # Code:
770  is($deref->(5), 39);
771  is(&$deref(6), 40);
772  sub xxx_goto { goto &$deref }
773  is(xxx_goto(7), 41);
774  my $srt = bless { c => sub {$b <=> $a}
775		  }, 'deref';
776  *srt = \&$srt;
777  my @sorted = sort srt 11, 2, 5, 1, 22;
778  is("@sorted", '22 11 5 2 1');
779  # Scalar
780  is($$deref, 123);
781  # Code
782  @sorted = sort $srt 11, 2, 5, 1, 22;
783  is("@sorted", '22 11 5 2 1');
784  # Array
785  is("@$deref", '11 12 13');
786  is($#$deref, '2');
787  my $l = @$deref;
788  is($l, 3);
789  is($deref->[2], '13');
790  $l = pop @$deref;
791  is($l, 13);
792  $l = 1;
793  is($deref->[$l], '12');
794  # Repeated dereference
795  my $double = bless { h => $deref,
796		     }, 'deref';
797  is($double->{foo}, 5);
798}
799
800{
801  package two_refs;
802  use overload '%{}' => \&gethash, '@{}' => sub { ${shift()} };
803  sub new { 
804    my $p = shift; 
805    bless \ [@_], $p;
806  }
807  sub gethash {
808    my %h;
809    my $self = shift;
810    tie %h, ref $self, $self;
811    \%h;
812  }
813
814  sub TIEHASH { my $p = shift; bless \ shift, $p }
815  my %fields;
816  my $i = 0;
817  $fields{$_} = $i++ foreach qw{zero one two three};
818  sub STORE { 
819    my $self = ${shift()};
820    my $key = $fields{shift()};
821    defined $key or die "Out of band access";
822    $$self->[$key] = shift;
823  }
824  sub FETCH { 
825    my $self = ${shift()};
826    my $key = $fields{shift()};
827    defined $key or die "Out of band access";
828    $$self->[$key];
829  }
830}
831
832my $bar = new two_refs 3,4,5,6;
833$bar->[2] = 11;
834is($bar->{two}, 11);
835$bar->{three} = 13;
836is($bar->[3], 13);
837
838{
839  package two_refs_o;
840  @ISA = ('two_refs');
841}
842
843$bar = new two_refs_o 3,4,5,6;
844$bar->[2] = 11;
845is($bar->{two}, 11);
846$bar->{three} = 13;
847is($bar->[3], 13);
848
849{
850  package two_refs1;
851  use overload '%{}' => sub { ${shift()}->[1] },
852               '@{}' => sub { ${shift()}->[0] };
853  sub new { 
854    my $p = shift; 
855    my $a = [@_];
856    my %h;
857    tie %h, $p, $a;
858    bless \ [$a, \%h], $p;
859  }
860  sub gethash {
861    my %h;
862    my $self = shift;
863    tie %h, ref $self, $self;
864    \%h;
865  }
866
867  sub TIEHASH { my $p = shift; bless \ shift, $p }
868  my %fields;
869  my $i = 0;
870  $fields{$_} = $i++ foreach qw{zero one two three};
871  sub STORE { 
872    my $a = ${shift()};
873    my $key = $fields{shift()};
874    defined $key or die "Out of band access";
875    $a->[$key] = shift;
876  }
877  sub FETCH { 
878    my $a = ${shift()};
879    my $key = $fields{shift()};
880    defined $key or die "Out of band access";
881    $a->[$key];
882  }
883}
884
885$bar = new two_refs_o 3,4,5,6;
886$bar->[2] = 11;
887is($bar->{two}, 11);
888$bar->{three} = 13;
889is($bar->[3], 13);
890
891{
892  package two_refs1_o;
893  @ISA = ('two_refs1');
894}
895
896$bar = new two_refs1_o 3,4,5,6;
897$bar->[2] = 11;
898is($bar->{two}, 11);
899$bar->{three} = 13;
900is($bar->[3], 13);
901
902{
903  package B;
904  use overload bool => sub { ${+shift} };
905}
906
907my $aaa;
908{ my $bbbb = 0; $aaa = bless \$bbbb, B }
909
910is !$aaa, 1;
911
912unless ($aaa) {
913  pass();
914} else {
915  fail();
916}
917
918# check that overload isn't done twice by join
919{ my $c = 0;
920  package Join;
921  use overload '""' => sub { $c++ };
922  my $x = join '', bless([]), 'pq', bless([]);
923  main::is $x, '0pq1';
924};
925
926# Test module-specific warning
927{
928    # check the Odd number of arguments for overload::constant warning
929    my $a = "" ;
930    local $SIG{__WARN__} = sub {$a = $_[0]} ;
931    $x = eval ' overload::constant "integer" ; ' ;
932    is($a, "");
933    use warnings 'overload' ;
934    $x = eval ' overload::constant "integer" ; ' ;
935    like($a, qr/^Odd number of arguments for overload::constant at/);
936}
937
938{
939    # check the '$_[0]' is not an overloadable type warning
940    my $a = "" ;
941    local $SIG{__WARN__} = sub {$a = $_[0]} ;
942    $x = eval ' overload::constant "fred" => sub {} ; ' ;
943    is($a, "");
944    use warnings 'overload' ;
945    $x = eval ' overload::constant "fred" => sub {} ; ' ;
946    like($a, qr/^'fred' is not an overloadable type at/);
947}
948
949{
950    # check the '$_[1]' is not a code reference warning
951    my $a = "" ;
952    local $SIG{__WARN__} = sub {$a = $_[0]} ;
953    $x = eval ' overload::constant "integer" => 1; ' ;
954    is($a, "");
955    use warnings 'overload' ;
956    $x = eval ' overload::constant "integer" => 1; ' ;
957    like($a, qr/^'1' is not a code reference at/);
958}
959
960{
961    # check the invalid argument warning [perl #74098]
962    my $a = "" ;
963    local $SIG{__WARN__} = sub {$a = $_[0]} ;
964    $x = eval ' use overload "~|_|~" => sub{} ' ;
965    eval ' no overload "~|_|~" ' ;
966    is($a, "");
967    use warnings 'overload' ;
968    $x = eval ' use overload "~|_|~" => sub{} ' ;
969    like($a, qr/^overload arg '~\|_\|~' is invalid at \(eval \d+\) line /,
970	'invalid arg warning');
971    undef $a;
972    eval ' no overload "~|_|~" ' ;
973    like($a, qr/^overload arg '~\|_\|~' is invalid at \(eval \d+\) line /,
974	'invalid arg warning');
975}
976
977{
978  my $c = 0;
979  package ov_int1;
980  use overload '""'    => sub { 3+shift->[0] },
981               '0+'    => sub { 10+shift->[0] },
982               'int'   => sub { 100+shift->[0] };
983  sub new {my $p = shift; bless [shift], $p}
984
985  package ov_int2;
986  use overload '""'    => sub { 5+shift->[0] },
987               '0+'    => sub { 30+shift->[0] },
988               'int'   => sub { 'ov_int1'->new(1000+shift->[0]) };
989  sub new {my $p = shift; bless [shift], $p}
990
991  package noov_int;
992  use overload '""'    => sub { 2+shift->[0] },
993               '0+'    => sub { 9+shift->[0] };
994  sub new {my $p = shift; bless [shift], $p}
995
996  package main;
997
998  my $x = new noov_int 11;
999  my $int_x = int $x;
1000  main::is("$int_x", 20);
1001  $x = new ov_int1 31;
1002  $int_x = int $x;
1003  main::is("$int_x", 131);
1004  $x = new ov_int2 51;
1005  $int_x = int $x;
1006  main::is("$int_x", 1054);
1007}
1008
1009# make sure that we don't infinitely recurse
1010{
1011  my $c = 0;
1012  package Recurse;
1013  use overload '""'    => sub { shift },
1014               '0+'    => sub { shift },
1015               'bool'  => sub { shift },
1016               fallback => 1;
1017  my $x = bless([]);
1018  # For some reason beyond me these have to be oks rather than likes.
1019  main::ok("$x" =~ /Recurse=ARRAY/);
1020  main::ok($x);
1021  main::ok($x+0 =~ qr/Recurse=ARRAY/);
1022}
1023
1024# BugID 20010422.003 (#6872)
1025package Foo;
1026
1027use overload
1028  'bool' => sub { return !$_[0]->is_zero() || undef; }
1029;
1030 
1031sub is_zero
1032  {
1033  my $self = shift;
1034  return $self->{var} == 0;
1035  }
1036
1037sub new
1038  {
1039  my $class = shift;
1040  my $self =  {};
1041  $self->{var} = shift;
1042  bless $self,$class;
1043  }
1044
1045package main;
1046
1047use strict;
1048
1049my $r = Foo->new(8);
1050$r = Foo->new(0);
1051
1052is(($r || 0), 0);
1053
1054package utf8_o;
1055
1056use overload 
1057  '""'  =>  sub { return $_[0]->{var}; }
1058  ;
1059  
1060sub new
1061  {
1062    my $class = shift;
1063    my $self =  {};
1064    $self->{var} = shift;
1065    bless $self,$class;
1066  }
1067
1068package main;
1069
1070
1071my $utfvar = new utf8_o 200.2.1;
1072is("$utfvar", 200.2.1); # 223 - stringify
1073is("a$utfvar", "a".200.2.1); # 224 - overload via sv_2pv_flags
1074
1075# 225..227 -- more %{} tests.  Hangs in 5.6.0, okay in later releases.
1076# Basically this example implements strong encapsulation: if Hderef::import()
1077# were to eval the overload code in the caller's namespace, the privatisation
1078# would be quite transparent.
1079package Hderef;
1080use overload '%{}' => sub { (caller(0))[0] eq 'Foo' ? $_[0] : die "zap" };
1081package Foo;
1082@Foo::ISA = 'Hderef';
1083sub new { bless {}, shift }
1084sub xet { @_ == 2 ? $_[0]->{$_[1]} :
1085	  @_ == 3 ? ($_[0]->{$_[1]} = $_[2]) : undef }
1086package main;
1087my $a = Foo->new;
1088$a->xet('b', 42);
1089is ($a->xet('b'), 42);
1090ok (!defined eval { $a->{b} });
1091like ($@, qr/zap/);
1092
1093{
1094   package t229;
1095   use overload '='  => sub { 42 },
1096                '++' => sub { my $x = ${$_[0]}; $_[0] };
1097   sub new { my $x = 42; bless \$x }
1098
1099   my $warn;
1100   {  
1101     local $SIG{__WARN__} = sub { $warn++ };
1102      my $x = t229->new;
1103      my $y = $x;
1104      eval { $y++ };
1105   }
1106   main::ok (!$warn);
1107}
1108
1109{
1110    my ($int, $out1, $out2);
1111    {
1112        BEGIN { $int = 0; overload::constant 'integer' => sub {$int++; 17}; }
1113        $out1 = 0;
1114        $out2 = 1;
1115    }
1116    is($int,  2,  "#24313");	# 230
1117    is($out1, 17, "#24313");	# 231
1118    is($out2, 17, "#24313");	# 232
1119}
1120
1121{
1122    package perl31793;
1123    use overload cmp => sub { 0 };
1124    package perl31793_fb;
1125    use overload cmp => sub { 0 }, fallback => 1;
1126    package main;
1127    my $o  = bless [], 'perl31793';
1128    my $of = bless [], 'perl31793_fb';
1129    my $no = bless [], 'no_overload';
1130    like(overload::StrVal(\"scalar"), qr/^SCALAR\(0x[0-9a-f]+\)$/);
1131    like(overload::StrVal([]),        qr/^ARRAY\(0x[0-9a-f]+\)$/);
1132    like(overload::StrVal({}),        qr/^HASH\(0x[0-9a-f]+\)$/);
1133    like(overload::StrVal(sub{1}),    qr/^CODE\(0x[0-9a-f]+\)$/);
1134    like(overload::StrVal(\*GLOB),    qr/^GLOB\(0x[0-9a-f]+\)$/);
1135    like(overload::StrVal(\$o),       qr/^REF\(0x[0-9a-f]+\)$/);
1136    like(overload::StrVal(qr/a/),     qr/^Regexp=REGEXP\(0x[0-9a-f]+\)$/);
1137    like(overload::StrVal($o),        qr/^perl31793=ARRAY\(0x[0-9a-f]+\)$/);
1138    like(overload::StrVal($of),       qr/^perl31793_fb=ARRAY\(0x[0-9a-f]+\)$/);
1139    like(overload::StrVal($no),       qr/^no_overload=ARRAY\(0x[0-9a-f]+\)$/);
1140}
1141
1142{
1143    package Numify;
1144    use overload (qw(0+ numify fallback 1));
1145
1146    sub new {
1147	my $val = $_[1];
1148	bless \$val, $_[0];
1149    }
1150
1151    sub numify { ${$_[0]} }
1152}
1153
1154# These all check that overloaded values, rather than reference addresses,
1155# are what are getting tested.
1156my ($two, $one, $un, $deux) = map {new Numify $_} 2, 1, 1, 2;
1157my ($ein, $zwei) = (1, 2);
1158
1159my %map = (one => 1, un => 1, ein => 1, deux => 2, two => 2, zwei => 2);
1160foreach my $op (qw(<=> == != < <= > >=)) {
1161    foreach my $l (keys %map) {
1162	foreach my $r (keys %map) {
1163	    my $ocode = "\$$l $op \$$r";
1164	    my $rcode = "$map{$l} $op $map{$r}";
1165
1166	    my $got = eval $ocode;
1167	    die if $@;
1168	    my $expect = eval $rcode;
1169	    die if $@;
1170	    is ($got, $expect, $ocode) or print "# $rcode\n";
1171	}
1172    }
1173}
1174{
1175    # check that overloading works in regexes
1176    {
1177	package Foo493;
1178	use overload
1179	    '""' => sub { "^$_[0][0]\$" },
1180	    '.'  => sub { 
1181		    bless [
1182			     $_[2]
1183			    ? (ref $_[1] ? $_[1][0] : $_[1]) . ':' .$_[0][0] 
1184			    : $_[0][0] . ':' . (ref $_[1] ? $_[1][0] : $_[1])
1185		    ], 'Foo493'
1186			};
1187    }
1188
1189    my $a = bless [ "a" ], 'Foo493';
1190    like('a', qr/$a/);
1191    like('x:a', qr/x$a/);
1192    like('x:a:=', qr/x$a=$/);
1193    like('x:a:a:=', qr/x$a$a=$/);
1194
1195}
1196
1197{
1198    {
1199        package QRonly;
1200        use overload qr => sub { qr/x/ }, fallback => 1;
1201    }
1202    {
1203        my $x = bless [], "QRonly";
1204
1205        # like tries to be too clever, and decides that $x-stringified
1206        # doesn't look like a regex
1207        ok("x" =~ $x, "qr-only matches");
1208        ok("y" !~ $x, "qr-only doesn't match what it shouldn't");
1209        ok("x" =~ /^(??{$x})$/, "qr-only with ?? matches");
1210        ok("y" !~ /^(??{$x})$/, "qr-only with ?? doesn't match what it shouldn't");
1211        ok("xx" =~ /x$x/, "qr-only matches with concat");
1212        like("$x", qr/^QRonly=ARRAY/, "qr-only doesn't have string overload");
1213
1214        my $qr = bless qr/y/, "QRonly";
1215        ok("x" =~ $qr, "qr with qr-overload uses overload");
1216        ok("y" !~ $qr, "qr with qr-overload uses overload");
1217	ok("x" =~ /^(??{$qr})$/, "qr with qr-overload with ?? uses overload");
1218	ok("y" !~ /^(??{$qr})$/, "qr with qr-overload with ?? uses overload");
1219        is("$qr", "".qr/y/, "qr with qr-overload stringify");
1220
1221        my $rx = $$qr;
1222        ok("y" =~ $rx, "bare rx with qr-overload doesn't overload match");
1223        ok("x" !~ $rx, "bare rx with qr-overload doesn't overload match");
1224        ok("y" =~ /^(??{$rx})$/, "bare rx with qr-overload with ?? doesn't overload match");
1225        ok("x" !~ /^(??{$rx})$/, "bare rx with qr-overload with ?? doesn't overload match");
1226        is("$rx", "".qr/y/, "bare rx with qr-overload stringify");
1227    }
1228    {
1229        package QRandSTR;
1230        use overload qr => sub { qr/x/ }, q/""/ => sub { "y" };
1231    }
1232    {
1233        my $x = bless [], "QRandSTR";
1234        ok("x" =~ $x, "qr+str uses qr for match");
1235        ok("y" !~ $x, "qr+str uses qr for match");
1236        ok("xx" =~ /x$x/, "qr+str uses qr for match with concat");
1237        is("$x", "y", "qr+str uses str for stringify");
1238
1239        my $qr = bless qr/z/, "QRandSTR";
1240        is("$qr", "y", "qr with qr+str uses str for stringify");
1241        ok("xx" =~ /x$x/, "qr with qr+str uses qr for match");
1242
1243        my $rx = $$qr;
1244        ok("z" =~ $rx, "bare rx with qr+str doesn't overload match");
1245        is("$rx", "".qr/z/, "bare rx with qr+str doesn't overload stringify");
1246    }
1247    {
1248        package QRany;
1249        use overload qr => sub { $_[0]->(@_) };
1250
1251        package QRself;
1252        use overload qr => sub { $_[0] };
1253    }
1254    {
1255        my $rx = bless sub { ${ qr/x/ } }, "QRany";
1256        ok("x" =~ $rx, "qr overload accepts a bare rx");
1257        ok("y" !~ $rx, "qr overload accepts a bare rx");
1258
1259        my $str = bless sub { "x" }, "QRany";
1260        ok(!eval { "x" =~ $str }, "qr overload doesn't accept a string");
1261        like($@, qr/^Overloaded qr did not return a REGEXP/, "correct error");
1262
1263        my $oqr = bless qr/z/, "QRandSTR";
1264        my $oqro = bless sub { $oqr }, "QRany";
1265        ok("z" =~ $oqro, "qr overload doesn't recurse");
1266
1267        my $qrs = bless qr/z/, "QRself";
1268        ok("z" =~ $qrs, "qr overload can return self");
1269    }
1270    {
1271        package STRonly;
1272        use overload q/""/ => sub { "x" };
1273
1274        package STRonlyFB;
1275        use overload q/""/ => sub { "x" }, fallback => 1;
1276    }
1277    {
1278        my $fb = bless [], "STRonlyFB";
1279        ok("x" =~ $fb, "qr falls back to \"\"");
1280        ok("y" !~ $fb, "qr falls back to \"\"");
1281
1282        my $nofb = bless [], "STRonly";
1283        ok("x" =~ $nofb, "qr falls back even without fallback");
1284        ok("y" !~ $nofb, "qr falls back even without fallback");
1285    }
1286}
1287
1288{
1289    my $twenty_three = 23;
1290    # Check that constant overloading propagates into evals
1291    BEGIN { overload::constant integer => sub { 23 } }
1292    is(eval "17", $twenty_three);
1293}
1294
1295{
1296    # Check readonliness of constants, whether shared hash key
1297    # scalars or no (brought up in bug #109744)
1298    BEGIN { overload::constant integer => sub { "main" }; }
1299    eval { ${\5} = 'whatever' };
1300    like $@, qr/^Modification of a read-only value attempted at /,
1301	'constant overloading makes read-only constants';
1302    BEGIN { overload::constant integer => sub { __PACKAGE__ }; }
1303    eval { ${\5} = 'whatever' };
1304    like $@, qr/^Modification of a read-only value attempted at /,
1305	'... even with shared hash key scalars';
1306}
1307
1308{
1309    package Sklorsh;
1310    use overload
1311	bool     => sub { shift->is_cool };
1312
1313    sub is_cool {
1314	$_[0]->{name} eq 'cool';
1315    }
1316
1317    sub delete {
1318	undef %{$_[0]};
1319	bless $_[0], 'Brap';
1320	return 1;
1321    }
1322
1323    sub delete_with_self {
1324	my $self = shift;
1325	undef %$self;
1326	bless $self, 'Brap';
1327	return 1;
1328    }
1329
1330    package Brap;
1331
1332    1;
1333
1334    package main;
1335
1336    my $obj;
1337    $obj = bless {name => 'cool'}, 'Sklorsh';
1338    $obj->delete;
1339    ok(eval {if ($obj) {1}; 1}, $@ || 'reblessed into nonexistent namespace');
1340
1341    $obj = bless {name => 'cool'}, 'Sklorsh';
1342    $obj->delete_with_self;
1343    ok (eval {if ($obj) {1}; 1}, $@);
1344    
1345    my $a = $b = {name => 'hot'};
1346    bless $b, 'Sklorsh';
1347    is(ref $a, 'Sklorsh');
1348    is(ref $b, 'Sklorsh');
1349    ok(!$b, "Expect overloaded boolean");
1350    ok(!$a, "Expect overloaded boolean");
1351}
1352
1353{
1354    package Flrbbbbb;
1355    use overload
1356	bool	 => sub { shift->{truth} eq 'yes' },
1357	'0+'	 => sub { shift->{truth} eq 'yes' ? '1' : '0' },
1358	'!'	 => sub { shift->{truth} eq 'no' },
1359	fallback => 1;
1360
1361    sub new { my $class = shift; bless { truth => shift }, $class }
1362
1363    package main;
1364
1365    my $yes = Flrbbbbb->new('yes');
1366    my $x;
1367    $x = 1 if $yes;			is($x, 1);
1368    $x = 2 unless $yes;			is($x, 1);
1369    $x = 3 if !$yes;			is($x, 1);
1370    $x = 4 unless !$yes;		is($x, 4);
1371
1372    my $no = Flrbbbbb->new('no');
1373    $x = 0;
1374    $x = 1 if $no;			is($x, 0);
1375    $x = 2 unless $no;			is($x, 2);
1376    $x = 3 if !$no;			is($x, 3);
1377    $x = 4 unless !$no;			is($x, 3);
1378
1379    $x = 0;
1380    $x = 1 if !$no && $yes;		is($x, 1);
1381    $x = 2 unless !$no && $yes;		is($x, 1);
1382    $x = 3 if $no || !$yes;		is($x, 1);
1383    $x = 4 unless $no || !$yes;		is($x, 4);
1384
1385    $x = 0;
1386    $x = 1 if !$no || !$yes;		is($x, 1);
1387    $x = 2 unless !$no || !$yes;	is($x, 1);
1388    $x = 3 if !$no && !$yes;		is($x, 1);
1389    $x = 4 unless !$no && !$yes;	is($x, 4);
1390}
1391
1392{
1393    use Scalar::Util 'weaken';
1394
1395    package Shklitza;
1396    use overload '""' => sub {"CLiK KLAK"};
1397
1398    package Ksshfwoom;
1399
1400    package main;
1401
1402    my ($obj, $ref);
1403    $obj = bless do {my $a; \$a}, 'Shklitza';
1404    $ref = $obj;
1405
1406    is ("$obj", "CLiK KLAK");
1407    is ("$ref", "CLiK KLAK");
1408
1409    weaken $ref;
1410    is ("$ref", "CLiK KLAK");
1411
1412    bless $obj, 'Ksshfwoom';
1413
1414    like ($obj, qr/^Ksshfwoom=/);
1415    like ($ref, qr/^Ksshfwoom=/);
1416
1417    undef $obj;
1418    is ($ref, undef);
1419}
1420
1421{
1422    package bit;
1423    # bit operations have overloadable assignment variants too
1424
1425    sub new { bless \$_[1], $_[0] }
1426
1427    use overload
1428          "&=" => sub { bit->new($_[0]->val . ' & ' . $_[1]->val) }, 
1429          "^=" => sub { bit->new($_[0]->val . ' ^ ' . $_[1]->val) },
1430          "|"  => sub { bit->new($_[0]->val . ' | ' . $_[1]->val) }, # |= by fallback
1431          ;
1432
1433    sub val { ${$_[0]} }
1434
1435    package main;
1436
1437    my $a = bit->new(my $va = 'a');
1438    my $b = bit->new(my $vb = 'b');
1439
1440    $a &= $b;
1441    is($a->val, 'a & b', "overloaded &= works");
1442
1443    my $c = bit->new(my $vc = 'c');
1444
1445    $b ^= $c;
1446    is($b->val, 'b ^ c', "overloaded ^= works");
1447
1448    my $d = bit->new(my $vd = 'd');
1449
1450    $c |= $d;
1451    is($c->val, 'c | d', "overloaded |= (by fallback) works");
1452}
1453
1454{
1455    # comparison operators with nomethod (bug 41546)
1456    my $warning = "";
1457    my $method;
1458
1459    package nomethod_false;
1460    use overload nomethod => sub { $method = 'nomethod'; 0 };
1461
1462    package nomethod_true;
1463    use overload nomethod => sub { $method= 'nomethod'; 'true' };
1464
1465    package main;
1466    local $^W = 1;
1467    local $SIG{__WARN__} = sub { $warning = $_[0] };
1468
1469    my $f = bless [], 'nomethod_false';
1470    ($warning, $method) = ("", "");
1471    is($f eq 'whatever', 0, 'nomethod makes eq return 0');
1472    is($method, 'nomethod');
1473
1474    my $t = bless [], 'nomethod_true';
1475    ($warning, $method) = ("", "");
1476    is($t eq 'whatever', 'true', 'nomethod makes eq return "true"');
1477    is($method, 'nomethod');
1478    is($warning, "", 'nomethod eq need not return number');
1479
1480    eval q{ 
1481        package nomethod_false;
1482        use overload cmp => sub { $method = 'cmp'; 0 };
1483    };
1484    $f = bless [], 'nomethod_false';
1485    ($warning, $method) = ("", "");
1486    ok($f eq 'whatever', 'eq falls back to cmp (nomethod not called)');
1487    is($method, 'cmp');
1488
1489    eval q{
1490        package nomethod_true;
1491        use overload cmp => sub { $method = 'cmp'; 'true' };
1492    };
1493    $t = bless [], 'nomethod_true';
1494    ($warning, $method) = ("", "");
1495    ok($t eq 'whatever', 'eq falls back to cmp (nomethod not called)');
1496    is($method, 'cmp');
1497    like($warning, qr/isn't numeric/, 'cmp should return number');
1498
1499}
1500
1501{
1502    # nomethod called for '!' after attempted fallback
1503    my $nomethod_called = 0;
1504
1505    package nomethod_not;
1506    use overload nomethod => sub { $nomethod_called = 'yes'; };
1507
1508    package main;
1509    my $o = bless [], 'nomethod_not';
1510    my $res = ! $o;
1511
1512    is($nomethod_called, 'yes', "nomethod() is called for '!'");
1513    is($res, 'yes', "nomethod(..., '!') return value propagates");
1514}
1515
1516{
1517    # Subtle bug pre 5.10, as a side effect of the overloading flag being
1518    # stored on the reference rather than the referent. Despite the fact that
1519    # objects can only be accessed via references (even internally), the
1520    # referent actually knows that it's blessed, not the references. So taking
1521    # a new, unrelated, reference to it gives an object. However, the
1522    # overloading-or-not flag was on the reference prior to 5.10, and taking
1523    # a new reference didn't (use to) copy it.
1524
1525    package kayo;
1526
1527    use overload '""' => sub {${$_[0]}};
1528
1529    sub Pie {
1530	return "$_[0], $_[1]";
1531    }
1532
1533    package main;
1534
1535    my $class = 'kayo';
1536    my $string = 'bam';
1537    my $crunch_eth = bless \$string, $class;
1538
1539    is("$crunch_eth", $string);
1540    is ($crunch_eth->Pie("Meat"), "$string, Meat");
1541
1542    my $wham_eth = \$string;
1543
1544    is("$wham_eth", $string,
1545       'This reference did not have overloading in 5.8.8 and earlier');
1546    is ($crunch_eth->Pie("Apple"), "$string, Apple");
1547
1548    my $class = ref $wham_eth;
1549    $class =~ s/=.*//;
1550
1551    # Bless it back into its own class!
1552    bless $wham_eth, $class;
1553
1554    is("$wham_eth", $string);
1555    is ($crunch_eth->Pie("Blackbird"), "$string, Blackbird");
1556}
1557
1558{
1559    package numify_int;
1560    use overload "0+" => sub { $_[0][0] += 1; 42 };
1561    package numify_self;
1562    use overload "0+" => sub { $_[0][0]++; $_[0] };
1563    package numify_other;
1564    use overload "0+" => sub { $_[0][0]++; $_[0][1] = bless [], 'numify_int' };
1565    package numify_by_fallback;
1566    use overload fallback => 1;
1567
1568    package main;
1569    my $o = bless [], 'numify_int';
1570    is(int($o), 42, 'numifies to integer');
1571    is($o->[0], 1, 'int() numifies only once');
1572
1573    my $aref = [];
1574    my $num_val = int($aref);
1575    my $r = bless $aref, 'numify_self';
1576    is(int($r), $num_val, 'numifies to self');
1577    is($r->[0], 1, 'int() numifies once when returning self');
1578
1579    my $s = bless [], 'numify_other';
1580    is(int($s), 42, 'numifies to numification of other object');
1581    is($s->[0], 1, 'int() numifies once when returning other object');
1582    is($s->[1][0], 1, 'returned object numifies too');
1583
1584    my $m = bless $aref, 'numify_by_fallback';
1585    is(int($m), $num_val, 'numifies to usual reference value');
1586    is(abs($m), $num_val, 'numifies to usual reference value');
1587    is(-$m, -$num_val, 'numifies to usual reference value');
1588    is(0+$m, $num_val, 'numifies to usual reference value');
1589    is($m+0, $num_val, 'numifies to usual reference value');
1590    is($m+$m, 2*$num_val, 'numifies to usual reference value');
1591    is(0-$m, -$num_val, 'numifies to usual reference value');
1592    is(1*$m, $num_val, 'numifies to usual reference value');
1593    is(int($m/1), $num_val, 'numifies to usual reference value');
1594    is($m%100, $num_val%100, 'numifies to usual reference value');
1595    is($m**1, $num_val, 'numifies to usual reference value');
1596
1597    is(abs($aref), $num_val, 'abs() of ref');
1598    is(-$aref, -$num_val, 'negative of ref');
1599    is(0+$aref, $num_val, 'ref addition');
1600    is($aref+0, $num_val, 'ref addition');
1601    is($aref+$aref, 2*$num_val, 'ref addition');
1602    is(0-$aref, -$num_val, 'subtraction of ref');
1603    is(1*$aref, $num_val, 'multiplicaton of ref');
1604    is(int($aref/1), $num_val, 'division of ref');
1605    is($aref%100, $num_val%100, 'modulo of ref');
1606    is($aref**1, $num_val, 'exponentiation of ref');
1607}
1608
1609{
1610    package CopyConstructorFallback;
1611    use overload
1612        '++'        => sub { "$_[0]"; $_[0] },
1613        fallback    => 1;
1614    sub new { bless {} => shift }
1615
1616    package main;
1617
1618    my $o = CopyConstructorFallback->new;
1619    my $x = $o++; # would segfault
1620    my $y = ++$o;
1621    is($x, $o, "copy constructor falls back to assignment (postinc)");
1622    is($y, $o, "copy constructor falls back to assignment (preinc)");
1623}
1624
1625# only scalar 'x' should currently overload
1626
1627{
1628    package REPEAT;
1629
1630    my ($x,$n, $nm);
1631
1632    use overload
1633	'x'        => sub { $x++; 1 },
1634	'0+'       => sub { $n++; 1 },
1635	'nomethod' => sub { $nm++; 1 },
1636	'fallback' => 0,
1637    ;
1638
1639    my $s = bless {};
1640
1641    package main;
1642
1643    my @a;
1644    my $count = 3;
1645
1646    ($x,$n,$nm) = (0,0,0);
1647    @a = ((1,2,$s) x $count);
1648    is("$x-$n-$nm", "0-0-0", 'repeat 1');
1649
1650    ($x,$n,$nm) = (0,0,0);
1651    @a = ((1,$s,3) x $count);
1652    is("$x-$n-$nm", "0-0-0", 'repeat 2');
1653
1654    ($x,$n,$nm) = (0,0,0);
1655    @a = ((1,2,3) x $s);
1656    is("$x-$n-$nm", "0-1-0", 'repeat 3');
1657}
1658
1659
1660
1661# RT #57012: magic items need to have mg_get() called before testing for
1662# overload. Lack of this means that overloaded values returned by eg a
1663# tied array didn't call overload methods.
1664# We test here both a tied array and scalar, since the implementation of
1665# tied  arrays (and hashes) is such that in rvalue context, mg_get is
1666# called prior to executing the op, while it isn't for a tied scalar.
1667# We also check that return values are correctly tainted.
1668# We try against two overload packages; one has all expected methods, the
1669# other uses only fallback methods.
1670
1671{
1672
1673    # @tests holds a list of test cases. Each elem is an array ref with
1674    # the following entries:
1675    #
1676    #  * the value that the overload method should return
1677    #
1678    #  * the expression to be evaled. %s is replaced with the
1679    #       variable being tested ($ta[0], $ts, or $plain)
1680    #
1681    #  * a string listing what functions we expect to be called.
1682    #       Each method appends its name in parentheses, so "(=)(+)" means
1683    #       we expect the copy constructor and then the add method to be
1684    #       called.
1685    #
1686    #  * like above, but what should be called for the fallback-only test
1687    #      (in this case, nomethod() identifies itself as "(NM:*)" where *
1688    #      is the op).  If this value is undef, fallback tests are skipped.
1689    #
1690    #  * An array ref of expected counts of calls to FETCH/STORE.
1691    #      The first three values are:
1692    #         1. the expected number of FETCHs for a tied array
1693    #         2. the expected number of FETCHs for a tied scalar
1694    #         3. the expected number of STOREs
1695    #       If there are a further three elements present, then
1696    #       these represent the expected counts for the fallback
1697    #       version of the tests. If absent, they are assumed to
1698    #       be the same as for the full method test
1699    #
1700    #  * Under the taint version of the tests,  whether we expect
1701    #       the result to be tainted (for example comparison ops
1702    #       like '==' don't return a tainted value, even if their
1703    #       args are.
1704    my @tests;
1705
1706    my %subs;
1707    my $funcs;
1708    my $use_int;
1709
1710    BEGIN {
1711	# A note on what methods to expect to be called, and
1712	# how many times FETCH/STORE is called:
1713	#
1714	# Mutating ops (+=, ++ etc) trigger a copy ('='), since
1715	# the code can't distinguish between something that's been copied:
1716	#    $a = foo->new(0); $b = $a; refcnt($$b) == 2
1717	# and overloaded objects stored in ties which will have extra
1718	# refcounts due to the tied_obj magic and entries on the tmps
1719	# stack when returning from FETCH etc. So we always copy.
1720
1721	# This accounts for a '=', and an extra STORE.
1722	# We also have a FETCH returning the final value from the eval,
1723	# plus a FETCH in the overload subs themselves: ($_[0][0])
1724	# triggers one. However, tied aggregates have a mechanism to prevent
1725	# multiple fetches between STOREs, which means that the tied
1726	# hash skips doing a FETCH during '='.
1727
1728	for (qw(+ - * / % ** << >> & | ^)) {
1729	    my $op = $_;
1730	    $op = '%%' if $op eq '%';
1731	    my $e = "%s $op= 3";
1732	    $subs{"$_="} = $e;
1733	    # ARRAY  FETCH: initial,        sub+=, eval-return,
1734	    # SCALAR FETCH: initial, sub=,  sub+=, eval-return,
1735	    # STORE:        copy, mutator
1736	    push @tests, [ 18, $e, "(=)($_=)", "(=)(NM:$_=)", [ 3, 4, 2 ], 1 ];
1737
1738	    $subs{$_} =
1739		"do { my \$arg = %s; \$_[2] ? (3 $op \$arg) : (\$arg $op 3) }";
1740	    # ARRAY  FETCH: initial
1741	    # SCALAR FETCH: initial eval-return,
1742	    push @tests, [ 18, "%s $op 3", "($_)", "(NM:$_)", [ 1, 2, 0 ], 1 ];
1743	    push @tests, [ 18, "3 $op %s", "($_)", "(NM:$_)", [ 1, 2, 0 ], 1 ];
1744	}
1745
1746	# these use string fallback rather than nomethod
1747	for (qw(x .)) {
1748	    my $op = $_;
1749	    my $e = "%s $op= 3";
1750	    $subs{"$_="} = $e;
1751	    # For normal case:
1752	    #   ARRAY  FETCH: initial,        sub+=, eval-return,
1753	    #   SCALAR FETCH: initial, sub=,  sub+=, eval-return,
1754	    #          STORE: copy, mutator
1755	    # for fallback, we just stringify, so eval-return and copy skipped
1756
1757	    push @tests, [ 18, $e, "(=)($_=)", '("")',
1758			    [ 3, 4, 2,     2, 3, 1 ], 1 ];
1759
1760	    $subs{$_} =
1761		"do { my \$arg = %s; \$_[2] ? (3 $op \$arg) : (\$arg $op 3) }";
1762	    # ARRAY  FETCH: initial
1763	    # SCALAR FETCH: initial eval-return,
1764	    # with fallback, we just stringify, so eval-return skipped,
1765	    #    but an extra FETCH happens in sub"", except for 'x',
1766	    #    which passes a copy of the RV to sub"", avoiding the
1767	    #    second FETCH
1768
1769	    push @tests, [ 18, "%s $op 3", "($_)", '("")',
1770			    [ 1, 2, 0,     1, ($_ eq '.' ? 2 : 1), 0 ], 1 ];
1771	    next if $_ eq 'x'; # repeat only overloads on LHS
1772	    push @tests, [ 18, "3 $op %s", "($_)", '("")',
1773			    [ 1, 2, 0,     1, 2, 0 ], 1 ];
1774	}
1775
1776	for (qw(++ --)) {
1777	    my $pre  = "$_%s";
1778	    my $post = "%s$_";
1779	    $subs{$_} = $pre;
1780	    push @tests,
1781		# ARRAY  FETCH: initial,        sub+=, eval-return,
1782		# SCALAR FETCH: initial, sub=,  sub+=, eval-return,
1783		# STORE:        copy, mutator
1784		[ 18, $pre, "(=)($_)(\"\")", "(=)(NM:$_)(\"\")", [ 3, 4, 2 ], 1 ],
1785		# ARRAY  FETCH: initial,        sub+=
1786		# SCALAR FETCH: initial, sub=,  sub+=
1787		# STORE:        copy, mutator
1788		[ 18, $post, "(=)($_)(\"\")", "(=)(NM:$_)(\"\")", [ 2, 3, 2 ], 1 ];
1789	}
1790
1791	# For the non-mutator ops, we have a initial FETCH,
1792	# an extra FETCH within the sub itself for the scalar option,
1793	# and no STOREs
1794
1795	for (qw(< <= >  >= == != lt le gt ge eq ne)) {
1796	    my $e = "%s $_ 3";
1797	    $subs{$_} = $e;
1798	    push @tests, [ 3, $e, "($_)", "(NM:$_)", [ 1, 2, 0 ], 0 ];
1799	}
1800	for (qw(<=> cmp)) {
1801	    my $e = "%s $_ 3";
1802	    $subs{$_} = $e;
1803	    push @tests, [ 3, $e, "($_)", "(NM:$_)", [ 1, 2, 0 ], 1 ];
1804	}
1805	for (qw(atan2)) {
1806	    my $e = "$_ %s, 3";
1807	    $subs{$_} = $e;
1808	    push @tests, [ 18, $e, "($_)", "(NM:$_)", [ 1, 2, 0 ], 1 ];
1809	}
1810	for (qw(cos sin exp abs log sqrt int ~)) {
1811	    my $e = "$_(%s)";
1812	    $subs{$_} = $e;
1813	    push @tests, [ 1.23, $e, "($_)",
1814		    ($_ eq 'int' ? '(0+)' : "(NM:$_)") , [ 1, 2, 0 ], 1 ];
1815	}
1816	for (qw(!)) {
1817	    my $e = "$_(%s)";
1818	    $subs{$_} = $e;
1819	    push @tests, [ 1.23, $e, "($_)", '(0+)', [ 1, 2, 0 ], 0 ];
1820	}
1821	for (qw(-)) {
1822	    my $e = "$_(%s)";
1823	    $subs{neg} = $e;
1824	    push @tests, [ 18, $e, '(neg)', '(NM:neg)', [ 1, 2, 0 ], 1 ];
1825	}
1826	my $e = '(%s) ? 1 : 0';
1827	$subs{bool} = $e;
1828	push @tests, [ 18, $e, '(bool)', '(0+)', [ 1, 2, 0 ], 0 ];
1829
1830	# note: this is testing unary qr, not binary =~
1831	$subs{qr} = '(qr/%s/)';
1832	push @tests, [ "abc", '"abc" =~ (%s)', '(qr)', '("")', [ 1, 2, 0 ], 0 ];
1833	push @tests, [ chr 256, 'chr(256) =~ (%s)', '(qr)', '("")',
1834	                                                  [ 1, 2, 0 ], 0 ];
1835
1836	$e = '"abc" ~~ (%s)';
1837	$subs{'~~'} = $e;
1838	push @tests, [ "abc", $e, '(~~)', '(NM:~~)', [ 1, 1, 0 ], 0 ];
1839
1840	$subs{'-X'} = 'do { my $f = (%s);'
1841		    . '$_[1] eq "r" ? (-r ($f)) :'
1842		    . '$_[1] eq "e" ? (-e ($f)) :'
1843		    . '$_[1] eq "f" ? (-f ($f)) :'
1844		    . '$_[1] eq "l" ? (-l ($f)) :'
1845		    . '$_[1] eq "t" ? (-t ($f)) :'
1846		    . '$_[1] eq "T" ? (-T ($f)) : 0;}';
1847	# Note - we don't care what these file tests return, as
1848	# long as the tied and untied versions return the same value.
1849	# The flags below are chosen to test all uses of tryAMAGICftest_MG
1850	for (qw(r e f l t T)) {
1851	    push @tests, [ 'TEST', "-$_ (%s)", '(-X)', '("")', [ 1, 2, 0 ], 0 ];
1852	}
1853
1854	$subs{'${}'} = '%s';
1855	push @tests, [ do {my $s=99; \$s}, '${%s}', '(${})', undef, [ 1, 1, 0 ], 0 ];
1856
1857	# we skip testing '@{}' here because too much of this test
1858	# framework involves array dereferences!
1859
1860	$subs{'%{}'} = '%s';
1861	push @tests, [ {qw(a 1 b 2 c 3)}, 'join "", sort keys %%{%s}',
1862			'(%{})', undef, [ 1, 1, 0 ], 0 ];
1863
1864	$subs{'&{}'} = '%s';
1865	push @tests, [ sub {99}, 'do {&{%s} for 1,2}',
1866			    '(&{})(&{})', undef, [ 2, 2, 0 ], 0 ];
1867
1868	our $RT57012A = 88;
1869	our $RT57012B;
1870	$subs{'*{}'} = '%s';
1871	push @tests, [ \*RT57012A, '*RT57012B = *{%s}; our $RT57012B',
1872		'(*{})', undef, [ 1, 1, 0 ], 0 ];
1873
1874	my $iter_text = ("some random text\n" x 100) . $^X;
1875	open my $iter_fh, '<', \$iter_text
1876	    or die "open of \$iter_text gave ($!)\n";
1877	$subs{'<>'} = '<$iter_fh>';
1878	push @tests, [ $iter_fh, '<%s>', '(<>)', undef, [ 1, 1, 0 ], 1 ];
1879	push @tests, [ $iter_fh,
1880		      'local *CORE::GLOBAL::glob = sub {}; eval q|<%s>|',
1881		      '(<>)', undef, [ 1, 1, 0 ], 1 ];
1882
1883	# eval should do tie, overload on its arg before checking taint */
1884	push @tests, [ '1;', 'eval q(eval %s); $@ =~ /Insecure/',
1885		'("")', '("")', [ 1, 2, 0 ], 0 ];
1886
1887
1888	for my $sub (keys %subs) {
1889	    no warnings 'experimental::smartmatch';
1890	    my $term = $subs{$sub};
1891	    my $t = sprintf $term, '$_[0][0]';
1892	    my $e ="sub { \$funcs .= '($sub)'; my \$r; if (\$use_int) {"
1893		. "use integer; \$r = ($t) } else { \$r = ($t) } \$r }";
1894	    $subs{$sub} = eval $e;
1895	    die "Compiling sub gave error:\n<$e>\n<$@>\n" if $@;
1896	}
1897    }
1898
1899    my $fetches;
1900    my $stores;
1901
1902    package RT57012_OV;
1903
1904    use overload
1905	%subs,
1906	"="   => sub { $funcs .= '(=)';  bless [ $_[0][0] ] },
1907	'0+'  => sub { $funcs .= '(0+)'; 0 + $_[0][0] },
1908	'""'  => sub { $funcs .= '("")'; "$_[0][0]"   },
1909	;
1910
1911    package RT57012_OV_FB; # only contains fallback conversion functions
1912
1913    use overload
1914	"="   => sub { $funcs .= '(=)';  bless [ $_[0][0] ] },
1915	'0+'  => sub { $funcs .= '(0+)'; 0 + $_[0][0] },
1916	'""'  => sub { $funcs .= '("")'; "$_[0][0]"   },
1917	"nomethod" => sub {
1918			$funcs .= "(NM:$_[3])";
1919			my $e = defined($_[1])
1920				? $_[3] eq 'atan2'
1921				    ? $_[2]
1922				       ? "atan2(\$_[1],\$_[0][0])"
1923				       : "atan2(\$_[0][0],\$_[1])"
1924				    : $_[2]
1925					? "\$_[1] $_[3] \$_[0][0]"
1926					: "\$_[0][0] $_[3] \$_[1]"
1927				: $_[3] eq 'neg'
1928				    ? "-\$_[0][0]"
1929				    : "$_[3](\$_[0][0])";
1930			my $r;
1931			no warnings 'experimental::smartmatch';
1932			if ($use_int) {
1933			    use integer; $r = eval $e;
1934			}
1935			else {
1936			    $r = eval $e;
1937			}
1938			::diag("eval of nomethod <$e> gave <$@>") if $@;
1939			$r;
1940		    }
1941
1942	;
1943
1944    package RT57012_TIE_S;
1945
1946    my $tie_val;
1947    sub TIESCALAR { bless [ bless [ $tie_val ], $_[1] ] }
1948    sub FETCH     { $fetches++; $_[0][0] }
1949    sub STORE     { $stores++;  $_[0][0] = $_[1] }
1950
1951    package RT57012_TIE_A;
1952
1953    sub TIEARRAY  { bless [] }
1954    sub FETCH     { $fetches++; $_[0][0] }
1955    sub STORE     { $stores++;  $_[0][$_[1]] = $_[2] }
1956
1957    package main;
1958
1959    for my $test (@tests) {
1960	my ($val, $sub_term, $exp_funcs, $exp_fb_funcs,
1961	    $exp_counts, $exp_taint) = @$test;
1962
1963	my $tainted_val;
1964	{
1965	    # create tainted version of $val (unless its a ref)
1966	    my $t = substr($^X,0,0);
1967	    my $t0 = $t."0";
1968	    my $val1 = $val; # use a copy to avoid stringifying original
1969	    $tainted_val = ref($val1) ? $val :
1970			($val1 =~ /^[\d\.]+$/) ? $val+$t0 : $val.$t;
1971	}
1972	$tie_val = $tainted_val;
1973
1974	for my $int ('', 'use integer; ') {
1975	    $use_int = ($int ne '');
1976	    my $plain = $tainted_val;
1977	    my $plain_term = $int . sprintf $sub_term, '$plain';
1978	    my $exp = do {no warnings 'experimental::smartmatch'; eval $plain_term };
1979	    diag("eval of plain_term <$plain_term> gave <$@>") if $@;
1980	    is(tainted($exp), $exp_taint,
1981			"<$plain_term> taint of expected return");
1982
1983	    for my $ov_pkg (qw(RT57012_OV RT57012_OV_FB)) {
1984		next if $ov_pkg eq 'RT57012_OV_FB'
1985			and  not defined $exp_fb_funcs;
1986		my ($exp_fetch_a, $exp_fetch_s, $exp_store) =
1987		    ($ov_pkg eq 'RT57012_OV' || @$exp_counts < 4)
1988			? @$exp_counts[0,1,2]
1989			: @$exp_counts[3,4,5];
1990
1991		tie my $ts, 'RT57012_TIE_S', $ov_pkg;
1992		tie my @ta, 'RT57012_TIE_A';
1993		$ta[0]    = bless [ $tainted_val ], $ov_pkg;
1994		my $oload = bless [ $tainted_val ], $ov_pkg;
1995
1996		for my $var ('$ta[0]', '$ts', '$oload',
1997			    ($sub_term eq '<%s>' ? '${ts}' : ())
1998		) {
1999
2000		    $funcs = '';
2001		    $fetches = 0;
2002		    $stores = 0;
2003
2004		    my $res_term  = $int . sprintf $sub_term, $var;
2005		    my $desc =  "<$res_term> $ov_pkg" ;
2006		    my $res = do { no warnings 'experimental::smartmatch'; eval $res_term };
2007		    diag("eval of res_term $desc gave <$@>") if $@;
2008		    # uniquely, the inc/dec ops return the original
2009		    # ref rather than a copy, so stringify it to
2010		    # find out if its tainted
2011		    $res = "$res" if $res_term =~ /\+\+|--/;
2012		    is(tainted($res), $exp_taint,
2013			    "$desc taint of result return");
2014		    is($res, $exp, "$desc return value");
2015		    my $fns =($ov_pkg eq 'RT57012_OV_FB')
2016				? $exp_fb_funcs : $exp_funcs;
2017		    if ($var eq '$oload' && $res_term !~ /oload(\+\+|--)/) {
2018			# non-tied overloading doesn't trigger a copy
2019			# except for post inc/dec
2020			$fns =~ s/^\(=\)//;
2021		    }
2022		    is($funcs, $fns, "$desc methods called");
2023		    next if $var eq '$oload';
2024		    my $exp_fetch = ($var eq '$ts') ?
2025			    $exp_fetch_s : $exp_fetch_a;
2026		    is($fetches, $exp_fetch, "$desc FETCH count");
2027		    is($stores, $exp_store, "$desc STORE count");
2028
2029		}
2030
2031	    }
2032	}
2033    }
2034}
2035
2036# Test overload from the main package
2037fresh_perl_is
2038 '$^W = 1; use overload q\""\ => sub {"ning"}; print bless []',
2039 'ning',
2040  { switches => ['-wl'], stderr => 1 },
2041 'use overload from the main package'
2042;
2043
2044{
2045    package blessed_methods;
2046    use overload '+' => sub {};
2047    bless overload::Method __PACKAGE__,'+';
2048    eval { overload::Method __PACKAGE__,'+' };
2049    ::is($@, '', 'overload::Method and blessed overload methods');
2050}
2051
2052{
2053    # fallback to 'cmp' and '<=>' with heterogeneous operands
2054    # [perl #71286]
2055    my $not_found = 'no method found';
2056    my $used = 0;
2057    package CmpBase;
2058    sub new {
2059        my $n = $_[1] || 0;
2060        bless \$n, ref $_[0] || $_[0];
2061    }
2062    sub cmp {
2063        $used = \$_[0];
2064        (${$_[0]} <=> ${$_[1]}) * ($_[2] ? -1 : 1);
2065    }
2066
2067    package NCmp;
2068    use parent '-norequire', 'CmpBase';
2069    use overload '<=>' => 'cmp';
2070
2071    package SCmp;
2072    use parent '-norequire', 'CmpBase';
2073    use overload 'cmp' => 'cmp';
2074
2075    package main;
2076    my $n = NCmp->new(5);
2077    my $s = SCmp->new(3);
2078    my $res;
2079
2080    eval { $res = $n > $s; };
2081    $res = $not_found if $@ =~ /$not_found/;
2082    is($res, 1, 'A>B using A<=> when B overloaded, no B<=>');
2083
2084    eval { $res = $s < $n; };
2085    $res = $not_found if $@ =~ /$not_found/;
2086    is($res, 1, 'A<B using B<=> when A overloaded, no A<=>');
2087
2088    eval { $res = $s lt $n; };
2089    $res = $not_found if $@ =~ /$not_found/;
2090    is($res, 1, 'A lt B using A:cmp when B overloaded, no B:cmp');
2091
2092    eval { $res = $n gt $s; };
2093    $res = $not_found if $@ =~ /$not_found/;
2094    is($res, 1, 'A gt B using B:cmp when A overloaded, no A:cmp');
2095
2096    my $o = NCmp->new(9);
2097    $res = $n < $o;
2098    is($used, \$n, 'A < B uses <=> from A in preference to B');
2099
2100    my $t = SCmp->new(7);
2101    $res = $s lt $t;
2102    is($used, \$s, 'A lt B uses cmp from A in preference to B');
2103}
2104
2105{
2106    # Combinatorial testing of 'fallback' and 'nomethod'
2107    # [perl #71286]
2108    package NuMB;
2109    use overload '0+' => sub { ${$_[0]}; },
2110        '""' => 'str';
2111    sub new {
2112        my $self = shift;
2113        my $n = @_ ? shift : 0;
2114        bless my $obj = \$n, ref $self || $self;
2115    }
2116    sub str {
2117        no strict qw/refs/;
2118        my $s = "(${$_[0]} ";
2119        $s .= "nomethod, " if defined ${ref($_[0]).'::(nomethod'};
2120        my $fb = ${ref($_[0]).'::()'};
2121        $s .= "fb=" . (defined $fb ? 0 + $fb : 'undef') . ")";
2122    }
2123    sub nomethod { "${$_[0]}.nomethod"; }
2124
2125    # create classes for tests
2126    package main;
2127    my @falls = (0, 'undef', 1);
2128    my @nomethods = ('', 'nomethod');
2129    my $not_found = 'no method found';
2130    for my $fall (@falls) {
2131        for my $nomethod (@nomethods) {
2132            my $nomethod_decl = $nomethod
2133                ? $nomethod . "=>'nomethod'," : '';
2134            eval qq{
2135                    package NuMB$fall$nomethod;
2136                    use parent '-norequire', qw/NuMB/;
2137                    use overload $nomethod_decl
2138                    fallback => $fall;
2139                };
2140        }
2141    }
2142
2143    # operation and precedence of 'fallback' and 'nomethod'
2144    # for all combinations with 2 overloaded operands
2145    for my $nomethod2 (@nomethods) {
2146        for my $nomethod1 (@nomethods) {
2147            for my $fall2 (@falls) {
2148                my $pack2 = "NuMB$fall2$nomethod2";
2149                for my $fall1 (@falls) {
2150                    my $pack1 = "NuMB$fall1$nomethod1";
2151                    my ($test, $out, $exp);
2152                    eval qq{
2153                            my \$x = $pack1->new(2);
2154                            my \$y = $pack2->new(3);
2155                            \$test = "\$x" . ' * ' . "\$y";
2156                            \$out = \$x * \$y;
2157                        };
2158                    $out = $not_found if $@ =~ /$not_found/;
2159                    $exp = $nomethod1 ? '2.nomethod' :
2160                         $nomethod2 ? '3.nomethod' :
2161                         $fall1 eq '1' && $fall2 eq '1' ? 6
2162                         : $not_found;
2163                    is($out, $exp, "$test --> $exp");
2164                }
2165            }
2166        }
2167    }
2168
2169    # operation of 'fallback' and 'nomethod'
2170    # where the other operand is not overloaded
2171    for my $nomethod (@nomethods) {
2172        for my $fall (@falls) {
2173            my ($test, $out, $exp);
2174            eval qq{
2175                    my \$x = NuMB$fall$nomethod->new(2);
2176                    \$test = "\$x" . ' * 3';
2177                    \$out = \$x * 3;
2178                };
2179            $out = $not_found if $@ =~ /$not_found/;
2180            $exp = $nomethod ? '2.nomethod' :
2181                $fall eq '1' ? 6
2182                : $not_found;
2183            is($out, $exp, "$test --> $exp");
2184
2185            eval qq{
2186                    my \$x = NuMB$fall$nomethod->new(2);
2187                    \$test = '3 * ' . "\$x";
2188                    \$out = 3 * \$x;
2189                };
2190            $out = $not_found if $@ =~ /$not_found/;
2191            is($out, $exp, "$test --> $exp");
2192        }
2193    }
2194}
2195
2196# since 5.6 overloaded <> was leaving an extra arg on the stack!
2197
2198{
2199    package Iter1;
2200    use overload '<>' => sub { 11 };
2201    package main;
2202    my $a = bless [], 'Iter1';
2203    my $x;
2204    my @a = (10, ($x = <$a>), 12);
2205    is ($a[0], 10, 'Iter1: a[0]');
2206    is ($a[1], 11, 'Iter1: a[1]');
2207    is ($a[2], 12, 'Iter1: a[2]');
2208    @a = (10, ($x .= <$a>), 12);
2209    is ($a[0],   10, 'Iter1: a[0] concat');
2210    is ($a[1], 1111, 'Iter1: a[1] concat');
2211    is ($a[2],   12, 'Iter1: a[2] concat');
2212}
2213
2214# Some tests for error messages
2215{
2216    package Justus;
2217    use overload '+' => 'justice';
2218    eval {"".bless[]};
2219    ::like $@, qr/^Can't resolve method "justice" overloading "\+" in p(?x:
2220                  )ackage "Justus" at /,
2221      'Error message when explicitly named overload method does not exist';
2222
2223    package JustUs;
2224    our @ISA = 'JustYou';
2225    package JustYou { use overload '+' => 'injustice'; }
2226    "JustUs"->${\"(+"};
2227    eval {"".bless []};
2228    ::like $@, qr/^Stub found while resolving method "\?{3}" overloadin(?x:
2229                  )g "\+" in package "JustUs" at /,
2230      'Error message when sub stub is encountered';
2231}
2232
2233{
2234    # check that the right number of stringifications
2235    # and the correct un-utf8-ifying happen on regex compile
2236    package utf8_match;
2237    my $c;
2238    use overload '""' => sub { $c++; $_[0][0] ? "^\x{100}\$" : "^A\$"; };
2239    my $o = bless [0], 'utf8_match';
2240
2241    $o->[0] = 0;
2242    $c = 0;
2243    ::ok("A" =~  "^A\$",	"regex stringify utf8=0 ol=0 bytes=0");
2244    ::ok("A" =~ $o,		"regex stringify utf8=0 ol=1 bytes=0");
2245    ::is($c, 1,			"regex stringify utf8=0 ol=1 bytes=0 count");
2246
2247    $o->[0] = 1;
2248    $c = 0;
2249    ::ok("\x{100}" =~ "^\x{100}\$",
2250				"regex stringify utf8=1 ol=0 bytes=0");
2251    ::ok("\x{100}" =~ $o,	"regex stringify utf8=1 ol=1 bytes=0");
2252    ::is($c, 1,			"regex stringify utf8=1 ol=1 bytes=0 count");
2253
2254    use bytes;
2255
2256    $o->[0] = 0;
2257    $c = 0;
2258    ::ok("A" =~  "^A\$",	"regex stringify utf8=0 ol=0 bytes=1");
2259    ::ok("A" =~ $o,		"regex stringify utf8=0 ol=1 bytes=1");
2260    ::is($c, 1,			"regex stringify utf8=0 ol=1 bytes=1 count");
2261
2262    $o->[0] = 1;
2263    $c = 0;
2264    ::ok(main::byte_utf8a_to_utf8n("\xc4\x80") =~ "^\x{100}\$",
2265				"regex stringify utf8=1 ol=0 bytes=1");
2266    ::ok(main::byte_utf8a_to_utf8n("\xc4\x80") =~ $o,	"regex stringify utf8=1 ol=1 bytes=1");
2267    ::is($c, 1,			"regex stringify utf8=1 ol=1 bytes=1 count");
2268
2269
2270}
2271
2272# [perl #40333]
2273# overload::Overloaded should not use a ->can designed for autoloading.
2274# This example attempts to be as realistic as possible.  The o class has a
2275# default singleton object, but can have instances, too.  The proxy class
2276# represents proxies for o objects, but class methods delegate to the
2277# singleton.
2278# overload::Overloaded used to return incorrect results for proxy objects.
2279package proxy {
2280    sub new { bless [$_[1]], $_[0] }
2281    sub AUTOLOAD {
2282       our $AUTOLOAD =~ s/.*:://;
2283       &_self->$AUTOLOAD;
2284    }
2285    sub can      { SUPER::can{@_} || &_self->can($_[1]) }
2286    sub _self { ref $_[0] ? $_[0][0] : $o::singleton }
2287}
2288package o     { use overload '""' => sub { 'keck' };
2289                sub new { bless[], $_[0] }
2290                our $singleton = o->new; }
2291ok !overload::Overloaded(new proxy new o),
2292 'overload::Overloaded does not incorrectly return true for proxy classes';
2293
2294# Another test, based on the type of explosive test class for which
2295# perl #40333 was filed.
2296{
2297    package broken_can;
2298    sub can {}
2299    use overload '""' => sub {"Ahoy!"};
2300
2301    package main;
2302    my $obj = bless [], 'broken_can';
2303    ok(overload::Overloaded($obj));
2304}
2305
2306sub eleventative::cos { 'eleven' }
2307sub twelvetative::abs { 'twelve' }
2308sub thirteentative::abs { 'thirteen' }
2309sub fourteentative::abs { 'fourteen' }
2310@eleventative::ISA = twelvetative::;
2311{
2312    my $o = bless [], 'eleventative';
2313    eval 'package eleventative; use overload map +($_)x2, cos=>abs=>';
2314    is cos $o, 'eleven', 'overloading applies to object blessed before';
2315    bless [], 'eleventative';
2316    is cos $o, 'eleven',
2317      'ovrld applies to previously-blessed obj after other obj is blessed';
2318    $o = bless [], 'eleventative';
2319    *eleventative::cos = sub { 'ten' };
2320    is cos $o, 'ten', 'method changes affect overloading';
2321    @eleventative::ISA = thirteentative::;
2322    is abs $o, 'thirteen', 'isa changes affect overloading';
2323    bless $o, 'fourteentative';
2324    @fourteentative::ISA = 'eleventative';
2325    is abs $o, 'fourteen', 'isa changes can turn overloading on';
2326}
2327
2328# no overload "fallback";
2329{ package phake;
2330  use overload fallback => 1, '""' => sub { 'arakas' };
2331  no overload 'fallback';
2332}
2333$a = bless [], 'phake';
2334is "$a", "arakas",
2335    'no overload "fallback" does not stop overload from working';
2336ok !eval { () = $a eq 'mpizeli'; 1 },
2337    'no overload "fallback" resets fallback to undef on overloaded class';
2338{ package ent; use overload fallback => 0, abs => sub{};
2339  our@ISA = 'huorn';
2340  package huorn;
2341  use overload fallback => 1;
2342  package ent;
2343  no overload "fallback"; # disable previous declaration
2344}
2345$a = bless [], ent::;
2346is eval {"$a"}, overload::StrVal($a),
2347    'no overload undoes fallback declaration completetly'
2348 or diag $@;
2349
2350# inherited fallback
2351{
2352 package pervyy;
2353 our @ISA = 'vtoryy';
2354 use overload "abs" =>=> sub {};
2355 package vtoryy;
2356 use overload fallback => 1, 'sin' =>=> sub{}
2357}
2358$a = bless [], pervyy::;
2359is eval {"$a"}, overload::StrVal($a),
2360 'fallback is inherited by classes that have their own overloading'
2361 or diag $@;
2362
2363# package separators in method names
2364{
2365 package mane;
2366 use overload q\""\ => "bear::strength";
2367 use overload bool  => "bear'bouillon";
2368}
2369@bear::ISA = 'food';
2370sub food::strength { 'twine' }
2371sub food::bouillon { 0 }
2372$a = bless[], mane::;
2373is eval { "$a" }, 'twine', ':: in method name' or diag $@;
2374is eval { !$a  },   1,      "' in method name" or diag $@;
2375
2376# [perl #113050] Half of CPAN assumes fallback is under "()"
2377{
2378  package dodo;
2379  use overload '+' => sub {};
2380  no strict;
2381  *{"dodo::()"} = sub{};
2382  ${"dodo::()"} = 1;
2383}
2384$a = bless [],'dodo';
2385is eval {"$a"}, overload::StrVal($a), 'fallback is stored under "()"';
2386
2387# [perl #47119]
2388{
2389    my $context;
2390
2391    {
2392        package Splitter;
2393        use overload '<>' => \&chars;
2394
2395        sub new {
2396            my $class = shift;
2397            my ($string) = @_;
2398            bless \$string, $class;
2399        }
2400
2401        sub chars {
2402            my $self = shift;
2403            my @chars = split //, $$self;
2404            $context = wantarray;
2405            return @chars;
2406        }
2407    }
2408
2409    my $obj = Splitter->new('bar');
2410
2411    $context = 42; # not 1, '', or undef
2412
2413    my @foo = <$obj>;
2414    is($context, 1, "list context (readline list)");
2415    is(scalar(@foo), 3, "correct result (readline list)");
2416    is($foo[0], 'b', "correct result (readline list)");
2417    is($foo[1], 'a', "correct result (readline list)");
2418    is($foo[2], 'r', "correct result (readline list)");
2419
2420    $context = 42;
2421
2422    my $foo = <$obj>;
2423    ok(defined($context), "scalar context (readline scalar)");
2424    is($context, '', "scalar context (readline scalar)");
2425    is($foo, 3, "correct result (readline scalar)");
2426
2427    $context = 42;
2428
2429    <$obj>;
2430    ok(!defined($context), "void context (readline void)");
2431
2432    $context = 42;
2433
2434    my @bar = <${obj}>;
2435    is($context, 1, "list context (glob list)");
2436    is(scalar(@bar), 3, "correct result (glob list)");
2437    is($bar[0], 'b', "correct result (glob list)");
2438    is($bar[1], 'a', "correct result (glob list)");
2439    is($bar[2], 'r', "correct result (glob list)");
2440
2441    $context = 42;
2442
2443    my $bar = <${obj}>;
2444    ok(defined($context), "scalar context (glob scalar)");
2445    is($context, '', "scalar context (glob scalar)");
2446    is($bar, 3, "correct result (glob scalar)");
2447
2448    $context = 42;
2449
2450    <${obj}>;
2451    ok(!defined($context), "void context (glob void)");
2452}
2453{
2454    my $context;
2455
2456    {
2457        package StringWithContext;
2458        use overload '""' => \&stringify;
2459
2460        sub new {
2461            my $class = shift;
2462            my ($string) = @_;
2463            bless \$string, $class;
2464        }
2465
2466        sub stringify {
2467            my $self = shift;
2468            $context = wantarray;
2469            return $$self;
2470        }
2471    }
2472
2473    my $obj = StringWithContext->new('bar');
2474
2475    $context = 42;
2476
2477    my @foo = "".$obj;
2478    ok(defined($context), "scalar context (stringify list)");
2479    is($context, '', "scalar context (stringify list)");
2480    is(scalar(@foo), 1, "correct result (stringify list)");
2481    is($foo[0], 'bar', "correct result (stringify list)");
2482
2483    $context = 42;
2484
2485    my $foo = "".$obj;
2486    ok(defined($context), "scalar context (stringify scalar)");
2487    is($context, '', "scalar context (stringify scalar)");
2488    is($foo, 'bar', "correct result (stringify scalar)");
2489
2490    $context = 42;
2491
2492    "".$obj;
2493
2494    is($context, '', "scalar context (stringify void)");
2495}
2496{
2497    my ($context, $swap);
2498
2499    {
2500        package AddWithContext;
2501        use overload '+' => \&add;
2502
2503        sub new {
2504            my $class = shift;
2505            my ($num) = @_;
2506            bless \$num, $class;
2507        }
2508
2509        sub add {
2510            my $self = shift;
2511            my ($other, $swapped) = @_;
2512            $context = wantarray;
2513            $swap = $swapped;
2514            return ref($self)->new($$self + $other);
2515        }
2516
2517        sub val { ${ $_[0] } }
2518    }
2519
2520    my $obj = AddWithContext->new(6);
2521
2522    $context = $swap = 42;
2523
2524    my @foo = $obj + 7;
2525    ok(defined($context), "scalar context (add list)");
2526    is($context, '', "scalar context (add list)");
2527    ok(defined($swap), "not swapped (add list)");
2528    is($swap, '', "not swapped (add list)");
2529    is(scalar(@foo), 1, "correct result (add list)");
2530    is($foo[0]->val, 13, "correct result (add list)");
2531
2532    $context = $swap = 42;
2533
2534    @foo = 7 + $obj;
2535    ok(defined($context), "scalar context (add list swap)");
2536    is($context, '', "scalar context (add list swap)");
2537    ok(defined($swap), "swapped (add list swap)");
2538    is($swap, 1, "swapped (add list swap)");
2539    is(scalar(@foo), 1, "correct result (add list swap)");
2540    is($foo[0]->val, 13, "correct result (add list swap)");
2541
2542    $context = $swap = 42;
2543
2544    my $foo = $obj + 7;
2545    ok(defined($context), "scalar context (add scalar)");
2546    is($context, '', "scalar context (add scalar)");
2547    ok(defined($swap), "not swapped (add scalar)");
2548    is($swap, '', "not swapped (add scalar)");
2549    is($foo->val, 13, "correct result (add scalar)");
2550
2551    $context = $swap = 42;
2552
2553    my $foo = 7 + $obj;
2554    ok(defined($context), "scalar context (add scalar swap)");
2555    is($context, '', "scalar context (add scalar swap)");
2556    ok(defined($swap), "swapped (add scalar swap)");
2557    is($swap, 1, "swapped (add scalar swap)");
2558    is($foo->val, 13, "correct result (add scalar swap)");
2559
2560    $context = $swap = 42;
2561
2562    $obj + 7;
2563
2564    ok(!defined($context), "void context (add void)");
2565    ok(defined($swap), "not swapped (add void)");
2566    is($swap, '', "not swapped (add void)");
2567
2568    $context = $swap = 42;
2569
2570    7 + $obj;
2571
2572    ok(!defined($context), "void context (add void swap)");
2573    ok(defined($swap), "swapped (add void swap)");
2574    is($swap, 1, "swapped (add void swap)");
2575
2576    $obj = AddWithContext->new(6);
2577
2578    $context = $swap = 42;
2579
2580    my @foo = $obj += 7;
2581    ok(defined($context), "scalar context (add assign list)");
2582    is($context, '', "scalar context (add assign list)");
2583    ok(!defined($swap), "not swapped and autogenerated (add assign list)");
2584    is(scalar(@foo), 1, "correct result (add assign list)");
2585    is($foo[0]->val, 13, "correct result (add assign list)");
2586    is($obj->val, 13, "correct result (add assign list)");
2587
2588    $obj = AddWithContext->new(6);
2589
2590    $context = $swap = 42;
2591
2592    my $foo = $obj += 7;
2593    ok(defined($context), "scalar context (add assign scalar)");
2594    is($context, '', "scalar context (add assign scalar)");
2595    ok(!defined($swap), "not swapped and autogenerated (add assign scalar)");
2596    is($foo->val, 13, "correct result (add assign scalar)");
2597    is($obj->val, 13, "correct result (add assign scalar)");
2598
2599    $obj = AddWithContext->new(6);
2600
2601    $context = $swap = 42;
2602
2603    $obj += 7;
2604
2605    ok(defined($context), "scalar context (add assign void)");
2606    is($context, '', "scalar context (add assign void)");
2607    ok(!defined($swap), "not swapped and autogenerated (add assign void)");
2608    is($obj->val, 13, "correct result (add assign void)");
2609
2610    $obj = AddWithContext->new(6);
2611
2612    $context = $swap = 42;
2613
2614    my @foo = ++$obj;
2615    ok(defined($context), "scalar context (add incr list)");
2616    is($context, '', "scalar context (add incr list)");
2617    ok(!defined($swap), "not swapped and autogenerated (add incr list)");
2618    is(scalar(@foo), 1, "correct result (add incr list)");
2619    is($foo[0]->val, 7, "correct result (add incr list)");
2620    is($obj->val, 7, "correct result (add incr list)");
2621
2622    $obj = AddWithContext->new(6);
2623
2624    $context = $swap = 42;
2625
2626    my $foo = ++$obj;
2627    ok(defined($context), "scalar context (add incr scalar)");
2628    is($context, '', "scalar context (add incr scalar)");
2629    ok(!defined($swap), "not swapped and autogenerated (add incr scalar)");
2630    is($foo->val, 7, "correct result (add incr scalar)");
2631    is($obj->val, 7, "correct result (add incr scalar)");
2632
2633    $obj = AddWithContext->new(6);
2634
2635    $context = $swap = 42;
2636
2637    ++$obj;
2638
2639    ok(defined($context), "scalar context (add incr void)");
2640    is($context, '', "scalar context (add incr void)");
2641    ok(!defined($swap), "not swapped and autogenerated (add incr void)");
2642    is($obj->val, 7, "correct result (add incr void)");
2643}
2644
2645# [perl #113010]
2646{
2647    {
2648        package OnlyFallback;
2649        use overload fallback => 0;
2650    }
2651    {
2652        my $obj = bless {}, 'OnlyFallback';
2653        my $died = !eval { "".$obj; 1 };
2654        my $err = $@;
2655        ok($died, "fallback of 0 causes error");
2656        like($err, qr/"\.": no method found/, "correct error");
2657    }
2658
2659    {
2660        package OnlyFallbackUndef;
2661        use overload fallback => undef;
2662    }
2663    {
2664        my $obj = bless {}, 'OnlyFallbackUndef';
2665        my $died = !eval { "".$obj; 1 };
2666        my $err = $@;
2667        ok($died, "fallback of undef causes error");
2668        # this one tries falling back to stringify before dying
2669        like($err, qr/"""": no method found/, "correct error");
2670    }
2671
2672    {
2673        package OnlyFallbackTrue;
2674        use overload fallback => 1;
2675    }
2676    {
2677        my $obj = bless {}, 'OnlyFallbackTrue';
2678        my $val;
2679        my $died = !eval { $val = "".$obj; 1 };
2680        my $err = $@;
2681        ok(!$died, "fallback of 1 doesn't cause error")
2682            || diag("got error of $err");
2683        like($val, qr/^OnlyFallbackTrue=HASH\(/, "stringified correctly");
2684    }
2685}
2686
2687{
2688    # Making Regexp class overloaded: avoid infinite recursion.
2689    # Do this in a separate process since it, well, overloads Regexp!
2690    fresh_perl_is(
2691	<<'EOF',
2692package Regexp;
2693use overload q{""} => sub {$_[0] };
2694package main;
2695my $r1 = qr/1/;
2696my $r2 = qr/ABC$r1/;
2697print $r2,"\n";
2698EOF
2699	'(?^:ABC(?^:1))',
2700	{ stderr => 1 },
2701	'overloaded REGEXP'
2702    );
2703}
2704
2705{
2706    # RT #121362
2707    # splitting the stash HV while rebuilding the overload cache gave
2708    # valgrind errors. This test code triggers such a split. It doesn't
2709    # actually test anything; its just there for valgrind to spot
2710    # problems.
2711
2712    package A_121362;
2713
2714    sub stringify { }
2715    use overload '""' => 'stringify';
2716
2717    package B_121362;
2718    our @ISA = qw(A_121362);
2719
2720    package main;
2721
2722    my $x = bless { }, 'B_121362';
2723
2724    for ('a'..'z') {
2725        delete $B_121362::{stringify}; # delete cache entry
2726        no strict 'refs';
2727        *{"B_121362::$_"}  = sub { };  # increase size of %B_121362
2728        my $y = $x->{value};       # trigger cache add to %B_121362
2729    }
2730    pass("RT 121362");
2731}
2732
2733package refsgalore {
2734    use overload
2735	'${}' => sub { \42  },
2736	'@{}' => sub { [43] },
2737	'%{}' => sub { { 44 => 45 } },
2738	'&{}' => sub { sub { 46 } };
2739}
2740{
2741    use feature 'postderef';
2742    tell myio; # vivifies *myio{IO} at compile time
2743    use constant ioref => bless *myio{IO}, refsgalore::;
2744    is ioref->$*, 42, '(overloaded constant that is not a scalar ref)->$*';
2745    is ioref->[0], 43, '(ovrld constant that is not an array ref)->[0]';
2746    is ioref->{44}, 45, "(ovrld const that is not a hash ref)->{key}";
2747    is ioref->(), 46, '(overloaded constant that is not a sub ref)->()';
2748}
2749
2750package xstack { use overload 'x' => sub { shift . " x " . shift },
2751                              '""'=> sub { "xstack" } }
2752is join(",", 1..3, scalar((bless([], 'xstack')) x 3, 1), 4..6),
2753  "1,2,3,1,4,5,6",
2754  '(...)x... in void cx with x overloaded [perl #121827]';
2755
2756package bitops {
2757    our @o;
2758    use overload do {
2759	my %o;
2760	for my $o (qw(& | ^ ~ &. |. ^. ~. &= |= ^= &.= |.= ^.=)) {
2761	    $o{$o} = sub {
2762		::ok !defined $_[3], "undef (or nonexistent) arg 3 for $o";
2763		push @o, $o, scalar @_, $_[4]//'u';
2764		$_[0]
2765	    }
2766	}
2767	%o, '=' => sub { bless [] };
2768    }
2769}
2770{
2771    use experimental 'bitwise';
2772    my $o = bless [], bitops::;
2773    $_ = $o & 0;
2774    $_ = $o | 0;
2775    $_ = $o ^ 0;
2776    $_ = ~$o;
2777    $_ = $o &. 0;
2778    $_ = $o |. 0;
2779    $_ = $o ^. 0;
2780    $_ = ~.$o;
2781    $o &= 0;
2782    $o |= 0;
2783    $o ^= 0;
2784    $o &.= 0;
2785    $o |.= 0;
2786    $o ^.= 0;
2787    # elems are in triplets: op, length of @_, numeric? (1/u for y/n)
2788    is "@bitops::o", '& 5 1 | 5 1 ^ 5 1 ~ 5 1 &. 3 u |. 3 u ^. 3 u ~. 3 u ' 		   . '&= 5 1 |= 5 1 ^= 5 1 &.= 3 u |.= 3 u ^.= 3 u',
2789       'experimental "bitwise" ops'
2790}
2791package bitops2 {
2792    our @o;
2793    use overload
2794	 nomethod => sub { push @o, $_[3], scalar @_, $_[4]//'u'; $_[0] },
2795	'=' => sub { bless [] };
2796}
2797{
2798    use experimental 'bitwise';
2799    my $o = bless [], bitops2::;
2800    $_ = $o & 0;
2801    $_ = $o | 0;
2802    $_ = $o ^ 0;
2803    $_ = ~$o;
2804    $_ = $o &. 0;
2805    $_ = $o |. 0;
2806    $_ = $o ^. 0;
2807    $_ = ~.$o;
2808    $o &= 0;
2809    $o |= 0;
2810    $o ^= 0;
2811    $o &.= 0;
2812    $o |.= 0;
2813    $o ^.= 0;
2814    # elems are in triplets: op, length of @_, numeric? (1/u for y/n)
2815    is "@bitops2::o", '& 5 1 | 5 1 ^ 5 1 ~ 5 1 &. 4 u |. 4 u ^. 4 u ~. 4 u ' 		    . '&= 5 1 |= 5 1 ^= 5 1 &.= 4 u |.= 4 u ^.= 4 u',
2816       'experimental "bitwise" ops with nomethod'
2817}
2818
2819package length_utf8 {
2820    use overload '""' => sub { "\x{100}" };
2821    my $o = bless [];
2822print length $o, "\n";
2823
2824    ::is length($o), 1, "overloaded utf8 length";
2825    ::is "$o", "\x{100}", "overloaded utf8 value";
2826}
2827
2828
2829{ # undefining the overload stash -- KEEP THIS TEST LAST
2830    package ant;
2831    use overload '+' => 'onion';
2832    $_ = \&overload::nil;
2833    undef %overload::;
2834    ()=0+bless[];
2835    ::ok(1, 'no crash when undefining %overload::');
2836}
2837
2838
2839# test various aspects of string concat overloading, especially where
2840# multiple concats etc are optimised into a single multiconcat op
2841
2842package Concat {
2843
2844    my $id;
2845
2846    # append a brief description of @_ to $id
2847    sub id {
2848        my @a = map ref $_      ?  "[" . $_->[0] . "]" :
2849                    !defined $_ ? "u"                  :
2850                    $_,
2851                @_;
2852        $id .= '(' . join (',', @a) . ')';
2853    }
2854
2855    use overload
2856        '.'  => sub {
2857                    id('.', @_);
2858                    my ($l, $r, $rev) = @_;
2859                    ($l, $r) = map ref $_ ? $_->[0] : $_, $l, $r;
2860                    ($l,$r) = ($r, $l) if $rev;
2861                    bless [ $l . $r ];
2862                },
2863
2864        '.=' => sub {
2865                    id('.=', @_);
2866                    my ($l, $r, $rev) = @_;
2867                    my ($ll, $rr) = map ref $_ ? $_->[0] : $_, $l, $r;
2868                    die "Unexpected reverse in .=" if $rev;
2869                    $l->[0] .= ref $r ? $r->[0] : $r;
2870                    $l;
2871                },
2872
2873        '=' => sub {
2874                    id('=', @_);
2875                    bless [ $_[0][0] ];
2876                },
2877
2878        '""' => sub {
2879                    id('""', @_);
2880                    $_[0][0];
2881                },
2882    ;
2883
2884    my $a = 'a';
2885    my $b = 'b';
2886    my $c = 'c';
2887    my $A = bless [ 'A' ];
2888    my $B = bless [ 'B' ];
2889    my $C = bless [ 'C' ];
2890
2891    my ($r, $R);
2892
2893
2894    # like cc, but with $is_ref set to 1
2895    sub c {
2896        my ($expr, $expect, $exp_id) = @_;
2897        cc($expr, $expect, 1, $exp_id);
2898    }
2899
2900    # eval $expr, and see if it returns $expect, and whether
2901    # the returned value is a ref ($is_ref). Finally, check that
2902    # $id, which has accumulated info from all overload method calls,
2903    # matches $exp_id.
2904
2905    sub cc {
2906        my ($expr, $expect, $is_ref, $exp_id) = @_;
2907
2908        $id = '';
2909        $r = 'r';
2910        $R = bless ['R'];
2911
2912        my $got = eval $expr;
2913        die "eval failed: $@" if $@;
2914        ::is "$got", $expect,   "expect: $expr";
2915        ::is $id, $exp_id,      "id:     $expr";
2916        ::is ref($got), ($is_ref ? 'Concat' : ''), "is_ref: $expr";
2917    }
2918
2919    # single concats
2920
2921    c '$r=$A.$b',       'Ab',   '(.,[A],b,)("",[Ab],u,)';
2922    c '$r=$a.$B',       'aB',   '(.,[B],a,1)("",[aB],u,)';
2923    c '$r=$A.$B',       'AB',   '(.,[A],[B],)("",[AB],u,)';
2924    c '$R.=$a',         'Ra',   '(.=,[R],a,u)("",[Ra],u,)';
2925    c '$R.=$A',         'RA',   '(.=,[R],[A],u)("",[RA],u,)';
2926
2927   # two concats
2928
2929    c '$r=$A.$b.$c',    'Abc',   '(.,[A],b,)(.=,[Ab],c,u)("",[Abc],u,)';
2930    c '$r=$A.($b.$c)',  'Abc',   '(.,[A],bc,)("",[Abc],u,)';
2931    c '$r=$a.$B.$c',    'aBc',   '(.,[B],a,1)(.=,[aB],c,u)("",[aBc],u,)';
2932    c '$r=$a.($B.$c)',  'aBc',   '(.,[B],c,)(.,[Bc],a,1)("",[aBc],u,)';
2933    c '$r=$a.$b.$C',    'abC',   '(.,[C],ab,1)("",[abC],u,)';
2934    c '$r=$a.($b.$C)',  'abC',   '(.,[C],b,1)(.,[bC],a,1)("",[abC],u,)';
2935
2936   # two concats plus mutator
2937
2938    c '$r.=$A.$b.$c',   'rAbc',  '(.,[A],b,)(.=,[Ab],c,u)(.,[Abc],r,1)'
2939                                .'("",[rAbc],u,)';
2940    c '$r.=$A.($b.$c)', 'rAbc',  '(.,[A],bc,)(.,[Abc],r,1)("",[rAbc],u,)';
2941    c '$r.=$a.$B.$c',   'raBc',  '(.,[B],a,1)(.=,[aB],c,u)(.,[aBc],r,1)'
2942                                .'("",[raBc],u,)';
2943    c '$r.=$a.($B.$c)', 'raBc',  '(.,[B],c,)(.,[Bc],a,1)(.,[aBc],r,1)'
2944                                .'("",[raBc],u,)';
2945    c '$r.=$a.$b.$C',   'rabC',  '(.,[C],ab,1)(.,[abC],r,1)("",[rabC],u,)';
2946    c '$r.=$a.($b.$C)', 'rabC',  '(.,[C],b,1)(.,[bC],a,1)(.,[abC],r,1)'
2947                                .'("",[rabC],u,)';
2948
2949    c '$R.=$A.$b.$c',   'RAbc',  '(.,[A],b,)(.=,[Ab],c,u)(.=,[R],[Abc],u)'
2950                                .'("",[RAbc],u,)';
2951    c '$R.=$A.($b.$c)', 'RAbc',  '(.,[A],bc,)(.=,[R],[Abc],u)("",[RAbc],u,)';
2952    c '$R.=$a.$B.$c',   'RaBc',  '(.,[B],a,1)(.=,[aB],c,u)(.=,[R],[aBc],u)'
2953                                .'("",[RaBc],u,)';
2954    c '$R.=$a.($B.$c)', 'RaBc',  '(.,[B],c,)(.,[Bc],a,1)(.=,[R],[aBc],u)'
2955                                .'("",[RaBc],u,)';
2956    c '$R.=$a.$b.$C',   'RabC',  '(.,[C],ab,1)(.=,[R],[abC],u)("",[RabC],u,)';
2957    c '$R.=$a.($b.$C)', 'RabC',  '(.,[C],b,1)(.,[bC],a,1)(.=,[R],[abC],u)'
2958                                .'("",[RabC],u,)';
2959
2960    # concat over assign
2961
2962    c '($R.=$a).$B.$c', 'RaBc',  '(.=,[R],a,u)(.,[Ra],[B],)(.=,[RaB],c,u)'
2963                                  .'("",[RaBc],u,)';
2964    ::is "$R", "Ra", 'R in concat over assign';
2965
2966
2967    # nested mutators
2968
2969    c '(($R.=$a).=$b).=$c', 'Rabc',  '(.=,[R],a,u)(=,[Ra],u,)(.=,[Ra],b,u)'
2970                                   . '(=,[Rab],u,)(.=,[Rab],c,u)("",[Rabc],u,)';
2971    c '(($R.=$a).=$B).=$c', 'RaBc',  '(.=,[R],a,u)(=,[Ra],u,)(.=,[Ra],[B],u)'
2972                                   . '(=,[RaB],u,)(.=,[RaB],c,u)("",[RaBc],u,)';
2973
2974    # plain SV on both LHS and RHS with RHS object
2975
2976    c '$r=$r.$A.$r',   'rAr',  '(.,[A],r,1)(.=,[rA],r,u)("",[rAr],u,)';
2977    c '$r.=$r.$A.$r',  'rrAr', '(.,[A],r,1)(.=,[rA],r,u)(.,[rAr],r,1)'
2978                              .'("",[rrAr],u,)';
2979
2980    # object on both LHS and RHS
2981
2982    c '$R.=$R',        'RR',    '(.=,[R],[R],u)("",[RR],u,)';
2983    c '$R.=$R.$b.$c',  'RRbc',  '(.,[R],b,)(.=,[Rb],c,u)(.=,[R],[Rbc],u)'
2984                               .'("",[RRbc],u,)';
2985    c '$R.=$a.$R.$c',  'RaRc',  '(.,[R],a,1)(.=,[aR],c,u)(.=,[R],[aRc],u)'
2986                               .'("",[RaRc],u,)'; 
2987    c '$R.=$a.$b.$R',  'RabR',  '(.,[R],ab,1)(.=,[R],[abR],u)("",[RabR],u,)';
2988
2989
2990    # sprintf shouldn't do concat overloading
2991
2992    cc '$r=sprintf("%s%s%s",$a,$B,$c)',  'aBc',  0, '("",[B],u,)';
2993    cc '$R=sprintf("%s%s%s",$a,$B,$c)',  'aBc',  0, '("",[B],u,)';
2994    cc '$r.=sprintf("%s%s%s",$a,$B,$c)', 'raBc', 0, '("",[B],u,)';
2995    cc '$R.=sprintf("%s%s%s",$a,$B,$c)', 'RaBc', 1, '("",[B],u,)(.=,[R],aBc,u)'
2996                                                   .'("",[RaBc],u,)';
2997
2998    # multiple constants should individually overload (RT #132385)
2999
3000    c '$r=$A."b"."c"', 'Abc',  '(.,[A],b,)(.=,[Ab],c,u)("",[Abc],u,)';
3001
3002    # ... except for this
3003    c '$R.="a"."b"',   'Rab',  '(.=,[R],ab,u)("",[Rab],u,)';
3004}
3005
3006# RT #132385
3007# The first arg of a reversed concat shouldn't be stringified:
3008#      $left . $right
3009#  where $right is overloaded, should invoke
3010#      concat($right, $left, 1)
3011#  rather than
3012#      concat($right, "$left", 1)
3013# There's a similar issue with
3014#      $left .= $right
3015# when left is overloaded
3016
3017package RT132385 {
3018
3019    use constant C => [ "constref" ];
3020
3021    use overload '.' => sub {
3022                            my ($l, $r, $rev) = @_;
3023                            ($l,$r) = ($r,$l) if $rev;
3024                            $l = ref $l ? $l->[0] : "$l";
3025                            $r = ref $r ? $r->[0] : "$r";
3026                            "$l-$r";
3027                        }
3028    ;
3029
3030    my $r1 = [ "ref1" ];
3031    my $r2 = [ "ref2" ];
3032    my $s1 =   "str1";
3033
3034    my $o = bless [ "obj" ];
3035
3036    # try variations that will call either pp_concat or pp_multiconcat,
3037    # with the ref as the first or a later arg
3038
3039    ::is($r1.$o,        "ref1-obj",             "RT #132385 r1.o");
3040    ::is($r1.$o.$s1 ,   "ref1-objstr1",         "RT #132385 r1.o.s1");
3041    ::is("const".$o.$s1 ,"const-objstr1",       "RT #132385 const.o.s1");
3042    ::is(C.$o.$s1       ,"constref-objstr1",    "RT #132385 C.o.s1");
3043
3044    ::like($r1.$r2.$o,   qr/^ARRAY\(0x\w+\)ARRAY\(0x\w+\)-obj/,
3045                                                "RT #132385 r1.r2.o");
3046
3047    # ditto with a mutator
3048    ::is($o .= $r1,     "obj-ref1",             "RT #132385 o.=r1");
3049}
3050
3051# the RHS of an overloaded .= should be passed as-is to the overload
3052# method, rather than being stringified or otherwise being processed in
3053# such a way that it triggers an undef warning
3054package RT132783 {
3055    use warnings;
3056    use overload '.=' => sub { return "foo" };
3057    my $w = 0;
3058    local $SIG{__WARN__} = sub { $w++ };
3059    my $undef;
3060    my $ov = bless [];
3061    $ov .= $undef;
3062    ::is($w, 0, "RT #132783 - should be no warnings");
3063}
3064
3065# changing the overloaded object to a plain string within an overload
3066# method should be permanent.
3067package RT132827 {
3068    use overload '""' => sub { $_[0] = "a" };
3069    my $ov = bless [];
3070    my $b = $ov . "b";
3071    ::is(ref \$ov, "SCALAR", "RT #132827");
3072}
3073
3074# RT #132793
3075# An arg like like "$b" in $overloaded .= "$b" should be stringified
3076# before being passed to the method
3077
3078package RT132793 {
3079    my $type;
3080    my $str = 0;
3081    use overload
3082        '.=' => sub { $type = ref(\$_[1]); "foo"; },
3083        '""' => sub { $str++;              "bar" };
3084
3085    my $a = bless {};
3086    my $b = bless {};
3087    $a .= "$b";
3088    ::is($type, "SCALAR", "RT #132793 type");
3089    ::is($str,  1,        "RT #132793 stringify count");
3090}
3091
3092# RT #132801
3093# A second RHS-not-stringified bug
3094
3095package RT132801 {
3096    my $type;
3097    my $str    = 0;
3098    my $concat = 0;
3099    use overload
3100        '.'  => sub { $concat++; bless []; },
3101        '""' => sub { $str++;    "bar" };
3102
3103    my $a = "A";
3104    my $b = bless [];
3105    my $c;
3106    $c = "$a-$b";
3107    ::is($concat, 1, "RT #132801 concat count");
3108    ::is($str,    1, "RT #132801 stringify count");
3109}
3110
3111# General testing of optimising away OP_STRINGIFY, and whether
3112# OP_MULTICONCAT emulates existing behaviour.
3113#
3114# It could well be argued that the existing behaviour is buggy, but
3115# for now emulate the old behaviour.
3116#
3117# In more detail:
3118#
3119# Since 5.000, any OP_STRINGIFY immediately following an OP_CONCAT
3120# is optimised away, on the assumption that since concat will always
3121# return a valid string anyway, it doesn't need stringifying.
3122# So in "$x", the stringify is needed, but on "$x$y" it isn't.
3123# This assumption is flawed once overloading has been introduced, since
3124# concat might return an overloaded object which still needs stringifying.
3125# However, this flawed behaviour is apparently needed by at least one
3126# module, and is tested for in opbasic/concat.t: see RT #124160.
3127#
3128# There is also a wart with the OPpTARGET_MY optimisation: specifically,
3129# in $lex = "...", if $lex is a lexical var, then a chain of 2 or more
3130# concats *doesn't* optimise away OP_STRINGIFY:
3131#
3132# $lex = "$x";        # stringifies
3133# $lex = "$x$y";      # doesn't stringify
3134# $lex = "$x$y$z..."; # stringifies
3135
3136package Stringify {
3137    my $count;
3138    use overload
3139        '.'  => sub {
3140                        my ($a, $b, $rev) = @_;
3141                        bless [ $rev ? "$b" . $a->[0] : $a->[0] . "$b" ];
3142            },
3143        '""' => sub {  $count++; $_[0][0] },
3144    ;
3145
3146    for my $test(
3147        [ 1, '$pkg   =  "$ov"' ],
3148        [ 1, '$lex   =  "$ov"' ],
3149        [ 1, 'my $a  =  "$ov"' ],
3150        [ 1, '$pkg  .=  "$ov"' ],
3151        [ 1, '$lex  .=  "$ov"' ],
3152        [ 1, 'my $a .=  "$ov"' ],
3153
3154        [ 0, '$pkg   =  "$ov$x"' ],
3155        [ 0, '$lex   =  "$ov$x"' ],
3156        [ 0, 'my $a  =  "$ov$x"' ],
3157        [ 0, '$pkg  .=  "$ov$x"' ],
3158        [ 0, '$lex  .=  "$ov$x"' ],
3159        [ 0, 'my $a .=  "$ov$x"' ],
3160
3161        [ 0, '$pkg   =  "$ov$x$y"' ],
3162        [ 1, '$lex   =  "$ov$x$y"' ],  # XXX note the anomaly
3163        [ 0, 'my $a  =  "$ov$x$y"' ],
3164        [ 0, '$pkg  .=  "$ov$x$y"' ],
3165        [ 0, '$lex  .=  "$ov$x$y"' ],
3166        [ 0, 'my $a .=  "$ov$x$y"' ],
3167    )
3168    {
3169        my ($stringify, $code) = @$test;
3170        our $pkg = 'P';
3171        my ($ov, $x, $y, $lex) = (bless(['OV']), qw(X Y L));
3172        $count = 0;
3173        eval "$code; 1" or die $@;
3174        ::is $count, $stringify, $code;
3175    }
3176}
3177
3178# RT #133789: in multiconcat with overload, the overloaded ref returned
3179# from the overload method was being assigned to the pad targ, causing
3180# a delay to the freeing of the object
3181
3182package RT33789 {
3183    use overload
3184        '.'  => sub { $_[0] }
3185    ;
3186
3187    my $destroy = 0;
3188    sub DESTROY { $destroy++ }
3189
3190    {
3191        my $o = bless [];
3192        my $result = '1' . ( '2' . ( '3' . ( '4' . ( '5' . $o ) ) ) );
3193    }
3194    ::is($destroy, 1, "RT #133789: delayed destroy");
3195}
3196